1,987 research outputs found

    Exact results for fidelity susceptibility of the quantum Ising model: The interplay between parity, system size, and magnetic field

    Full text link
    We derive an exact closed-form expression for fidelity susceptibility of even- and odd-sized quantum Ising chains in the transverse field. To this aim, we diagonalize the Ising Hamiltonian and study the gap between its positive and negative parity subspaces. We derive an exact closed-form expression for the gap and use it to identify the parity of the ground state. We point out misunderstanding in some of the former studies of fidelity susceptibility and discuss its consequences. Last but not least, we rigorously analyze the properties of the gap. For example, we derive analytical expressions showing its exponential dependence on the ratio between the system size and the correlation length.Comment: 11 pages, updated references, version accepted in JP

    New financial markets and their impact on raw material prices

    Get PDF
    The purpose of the study was to determine the impact of the Chinese financial market, which is a new market, on the exchange rates of commodity currencies and, thus, the prices of raw materials. For this purpose, an autoregressive distributed lag model (ARDL) was used. The results indicate that the Chinese stock market and futures market for the yuan (the Chinese Yuan Non-Deliverable Forward Transactions; CNY NDF market) had a significant impact on commodity currencies before the global financial crisis in 2008/09, then the effect widened to include more commodity currencies in the post-crisis period. Further evidence suggests that the CNY NDF market had a greater impact on commodity currencies than the Chinese stock market. Despite the significant position of the Chinese economy, research also indicates that the impact of Chinese financial markets on commodity currencies (raw material prices) is weaker than the impact of the US stock market and US dollar market.The purpose of the study was to determine the impact of the Chinese financial market, which is a new market, on the exchange rates of commodity currencies and, thus, the prices of raw materials. For this purpose, an autoregressive distributed lag model (ARDL) was used. The results indicate that the Chinese stock market and futures market for the yuan (the Chinese Yuan Non-Deliverable Forward Transactions; CNY NDF market) had a significant impact on commodity currencies before the global financial crisis in 2008/09, then the effect widened to include more commodity currencies in the post-crisis period. Further evidence suggests that the CNY NDF market had a greater impact on commodity currencies than the Chinese stock market. Despite the significant position of the Chinese economy, research also indicates that the impact of Chinese financial markets on commodity currencies (raw material prices) is weaker than the impact of the US stock market and US dollar market

    Quantum fidelity in the thermodynamic limit

    Full text link
    We study quantum fidelity, the overlap between two ground states of a many-body system, focusing on the thermodynamic regime. We show how drop of fidelity near a critical point encodes universal information about a quantum phase transition. Our general scaling results are illustrated in the quantum Ising chain for which a remarkably simple expression for fidelity is found.Comment: 4 pages, 4 figures, rearranged a bit to improve presentatio

    Asymptotic properties of solutions of some iterative functional inequalities

    Get PDF
    Continuous solutions of iterative linear inequalities of the first and second order are considered, belonging to a class FT\mathcal{F}_T of functions behaving at the origin as a prescribed function TT

    Sexual function and depressive symptoms in men with overt hyperthyroidism

    Get PDF
    Introduction: Although hyperthyroidism is characterised by female predominance, its presence may lead to the development of numerous complications in both sexes. This study was aimed at investigating sexual function and depressive symptoms in men with overt hyperthyroidism of autoimmune and non-autoimmune origin. Material and methods: The study population consisted of three age-matched groups: men with overt hyperthyroidism and Graves’ disease (group A; n = 20), men with overt hyperthyroidism and toxic multinodular goitre or toxic adenoma (group B; n = 21), and men with normal thyroid function (group C; n = 23). As well as measuring serum hormone levels and antibody titres, and determining calculated parameters of thyroid homeostasis, all included patients filled in questionnaires evaluating sexual function (International Index of ErectileFunction-15: IIEF-15) and assessing the presence and severity of depressive symptoms (Beck Depression Inventory-Second Edition – BDI-II). Results: Compared with control subjects, men with overt hyperthyroidism obtained lower scores for erectile function, intercourse satisfaction, orgasmic function and overall satisfaction. Scores for erectile function, orgasmic function, and sexual desire differed between both groups of men with thyroid hyperfunction and inversely correlated with thyrotropin receptor antibody titres. The BDI-II score was higher in patients with Graves’ disease than in men with normal thyroid function. Conclusions: The obtained results indicate that overt hyperthyroidism in men causes multidimensional impairment of sexual function, which is particularly pronounced if excessive hormone production results from Graves’ disease.

    Cardiometabolic risk factors in young women with macroprolactinaemia

    Get PDF
    Introduction: The predominance of high-molecular-weight forms of prolactin in plasma is referred to as macroprolactinaemia. Unlike monomeric hyperprolactinaemia, no previous study has investigated cardiometabolic risk factors in subjects with elevated macroprolactin content. Material and methods: We studied two age-, weight-, and blood pressure-matched groups of premenopausal women: 11 women with macroprolactinaemia and 11 women with prolactin levels within the reference range. The outcomes of interest included: glucose homeostasis markers, plasma lipids, as well as plasma levels of uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine, and 25-hydroxyvitamin D. Results: Circulating levels of hsCRP and 2-h postchallenge plasma glucose, as well as the homeostatic model assessment 1 of insulin resistance ratio, were higher, while levels of HDL cholesterol and 25-hydroxyvitamin D were lower in women with macroprolactinaemia than in women without elevated levels of prolactin. In women with elevated levels of big-big prolactin, values of hsCRP and 25-hydroxyvitamin D correlated with the degree of insulin resistance and, similarly to HDL cholesterol and 2-h postchallenge plasma glucose, with macroprolactin content. There were no differences between the study groups in concentrations of fasting glucose, total cholesterol, LDL cholesterol, triglycerides, uric acid, fibrinogen, and homocysteine. Conclusions: The obtained results indicate that young women with macroprolactinaemia seem to be characterised by slightly increased cardiometabolic risk

    Funkcjonowanie seksualne i objawy depresyjne u młodych mężczyzn z niedoczynnością tarczycy leczonych terapią skojarzoną z zastosowaniem lewotyroksyny i liotyroniny

    Get PDF
    Introduction: Both overt and subclinical hypothyroidism are often accompanied by sexual dysfunction. Despite improving male sexual functioning, levothyroxine treatment does not always restore all its aspects. The aim of this study was to compare male sexual function­ing and depressive symptoms between men with hypothyroidism receiving levothyroxine/liothyronine combination therapy and men receiving levothyroxine alone. Material and methods: The study population consisted of 21 young levothyroxine-treated men with clinical symptoms of hypothyroid­ism, in whom serum thyrotropin and thyroid hormone levels were within the normal limits. In 11 of these patients, levothyroxine was replaced with levothyroxine/liothyronine combination therapy, while the remaining ones (n = 10) continued levothyroxine treatment. Beyond measuring serum levels of thyrotropin, free thyroxine, free triiodothyronine, and prolactin, before the beginning of the study and six months later, all enrolled patients completed questionnaires evaluating male sexual function (International Index of Erectile Func­tion-15: IIEF-15) and assessing the presence and severity of depressive symptoms (Beck Depression Inventory-Second Edition — BDI-II). Results: The study included 10 patients from each group. At baseline, erectile function, intercourse satisfaction, orgasmic function, sexual desire and overall satisfaction, as well as the total BDI-II score did not differ between both groups. With the exception of an improvement in sexual desire, replacing levothyroxine with levothyroxine/liothyronine combination therapy did not affect sexual functioning and depressive symptoms. Conclusions: The obtained results suggest that levothyroxine/liothyronine combination therapy has a relatively mild effect on sexual functioning in levothyroxine-treated men with normal thyrotropin and thyroid hormone levels experiencing clinical symptoms of hypo­thyroidism.Wprowadzenie: Zarówno klinicznie jawnej jak i subklinicznej niedoczynności tarczycy często towarzyszy dysfunkcja seksualna. Pomimo poprawy, lewotyroksyna nie zawsze normalizuje funkcjonowanie seksualne w stanach niedoboru hormonów tarczycy. Celem badania było porównanie funkcjonowania seksualnego i objawów depresyjnych pomiędzy mężczyznami leczonymi zarówno lewotyroksyną i liotyroniną oraz mężczyznami otrzymującymi wyłącznie lewotyroksynę. Materiał i metody: Uczestnikami badania było 21 mężczyzn leczonych lewotyroksyną odczuwających objawy kliniczne niedoczynności tarczycy, pomimo mieszczących się w granicach normy stężeniach TSH i wolnych hormonów tarczycy. U 11 z nich w miejsce lewotyroksyny włączono preparat skojarzony zawierający lewotyroksynę i liotyroninę, podczas gdy pozostałych 10 pacjentów kontynuowało leczenie lewotyroksyną. Poza oceną stężenia w surowicy: TSH, wolnej tyroksyny, wolnej trijodotyroniny i prolaktyny, w dniu rozpoczęcia badania i sześć miesięcy później, wszyscy pacjenci wypełniali kwestionariusze oceniające funkcjonowanie seksualne (IIEF-15), jak również obecność i nasilenie objawów depresyjnych (BDI-II). Wyniki: W każdej grupie badanie ukończyło dziesięciu pacjentów. W warunkach wyjściowych funkcja erekcyjna, satysfakcja seksualna, jakość orgazmu, pożądanie, całkowita satysfakcja seksualna, jak również globalny wskaźnik BDI-II nie różniły się między grupami. Za wyjątkiem poprawy w zakresie libido, zastąpienie lewotyroksyny leczeniem skojarzonym nie wpływało na funkcjonowanie seksualne i objawy depresyjne. Wnioski: Uzyskane wyniki sugerują, iż terapia skojarzona lewotyroksyną i liotyroniną ma stosunkowo niewielki wpływ na funkcjonowanie seksualne mężczyzn odczuwających objawy niedoczynności tarczycy pomimo prawidłowego stężenia TSH i hormonów tarczycy

    Processes and the Resulting Water Quality in the Medium-Size Turawa Storage Reservoir after 60-Year Usage

    Get PDF
    The characteristics of water in the Turawa reservoir, one of the important storage reservoirs in Poland, were thoroughly studied. The reservoir and also the rivers flowing into the reservoir were monitored in the period 2004–2006 with respect to the basic physico-chemical parameters determining the quality of water such as water temperature, specific conductance, pH, biochemical oxygen demand (BOD5) and chemical oxygen demand (CODMn), water hardness, content of typical ions (sodium, potassium, sulphates, phosphates and chlorides), heavy metals, and so on. The observed seasonal and long-term changes of the parameters measured were discussed and the processes responsible for the changes suggested. The causes of the observed deterioration of the ecological status of the Turawa reservoir were given and the remedial operations proposed. The latter included improvement in the management of solid wastes and wastewater in the area, reducing the runoff of nutrients in the catchment, decrease in discharge of pollutants into the rivers flowing into the reservoir, removal of bottom sediments and also increasing the average water table and decreasing its fluctuations. The effect of the remedial operations will be further studied
    corecore