681 research outputs found

    Instabilities in the Flux Line Lattice of Anisotropic Superconductors

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    The stability of the flux line lattice has been investigated within anisotropic London theory. This is the first full-scale investigation of instabilities in the `chain' state. It has been found that the lattice is stable at large fields, but that instabilities occur as the field is reduced. The field at which these instabilities first arise, b∗(ϵ,θ)b^*(\epsilon,\theta), depends on the anisotropy ϵ\epsilon and the angle θ\theta at which the lattice is tilted away from the cc-axis. These instabilities initially occur at wavevector k∗(ϵ,θ)k^*(\epsilon,\theta), and the component of k∗k^* along the average direction of the flux lines, kzk_z, is always finite. As the instability occurs at finite kzk_z the dependence of the cutoff on kzk_z is important, and we have used a cutoff suggested by Sudb\ospace and Brandt. The instabilities only occur for values of the anisotropy ϵ\epsilon appropriate to a material like BSCCO, and not for anisotropies more appropriate to YBCO. The lower critical field Hc1(ϕ)H_{c_1}(\phi) is calculated as a function of the angle ϕ\phi at which the applied field is tilted away from the crystal axis. The presence of kinks in Hc1(ϕ)H_{c_1}(\phi) is seen to be related to instabilities in the equilibrium flux line structure.Comment: Extensively revised paper, with modified analysis of elastic instabilities. Calculation of the lower critical field is included, and the presence of kinks in Hc1H_{c_1} is seen to be related to the elastic instabilities. 29 pages including 16 figures, LaTeX with epsf styl

    Grotta Romanelli (Southern Italy, Apulia). Legacies and issues in excavating a key site for the Pleistocene of the Mediterranean

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    Grotta Romanelli, located on the Adriatic coast of southern Apulia (Italy), is considered a key site for the Mediterranean Pleistocene for its archaeological and palaeontological contents. The site, discovered in 1874, was re-evaluated only in 1900, when P. E. Stasi realised that it contained the first evidence of the Palaeolithic in Italy. Starting in 1914, G. A. Blanc led a pioneering excavation campaign, for the first-time using scientific methods applied to systematic palaeontological and stratigraphical studies. Blanc proposed a stratigraphic framework for the cave. Different dating methods (C-14 and U/Th) were used to temporally constrain the deposits. The extensive studies of the cave and its contents were mostly published in journals with limited distribution and access, until the end of the 1970s, when the site became forgotten. In 2015, with the permission of the authorities, a new excavation campaign began, led by a team from Sapienza University of Rome in collaboration with IGAG CNR and other research institutions. The research team had to deal with the consequences of more than 40 years of inactivity in the field and the combined effect of erosion and legal, as well as illegal, excavations. In this paper, we provide a database of all the information published during the first 70 years of excavations and highlight the outstanding problems and contradictions between the chronological and geomorphological evidence, the features of the faunal assemblages and the limestone artefacts

    The relationship between sulfur metabolism and tolerance of hexavalent chromium in Scenedesmus acutus (Spheropleales): Role of ATP sulfurylase

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    Sulfur availability and the end products of its metabolism, cysteine, glutathione and phytochelatins, play an important role in heavy metal tolerance, chromium included. Sulfate and chromate not only compete for the transporters but also for assimilation enzymes and chromium tolerance in various organisms has been associated to differences in this pathway. We investigated the mechanisms of Cr(VI)-tolerance increase induced by S-starvation focusing on the role of ATP sulfurylase (ATS) in two strains of Scenedesmus acutus with different chromium sensitivity. S-starvation enhances the defence potential by increasing sulfate uptake/assimilation and decreasing chromium uptake, thus suggesting a change in the transport system. We isolated two isoforms of the enzyme, SaATS1 and SaATS2, with different sensitivity to sulfur availability, and analysed them in S-sufficient and S-replete condition both in standard and in chromium supplemented medium. SaATS2 expression is different in the two strains and presumably marks a different sulfur perception/exploitation in the Cr-tolerant. Its induction and silencing are compatible with a role in the transient tolerance increase induced by S-starvation. This enzyme can however hardly be responsible for the large cysteine production of the Cr-tolerant strain after starvation, suggesting that cytosolic rather than chloroplastic cysteine production is differently regulated in the two strains

    Anti-inflammatory and wound healing effects of an essential oils-based bioadhesive gel after oral mucosa biopsies: preliminary results

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    Post-operative management of patients receiving oral biopsy includes the control of edema, pain, infection, and re-epithelization at the surgical site. This clinical study investigates the topical use of a bioadhesive gel, containing essential oils, to promote wound healing and prevent post-operative pain and infection, avoiding the need for surgical suture and chlorhexidine applications. Ten patients, who needed to receive oral biopsies ( 646 mm in diameter) for the diagnosis of mucosal oral lesions, were enrolled. The bioadhesive gel successfully controlled the post-surgical pain; at 1-week follow-up visit, no signs of infection nor side effects were reported and the surgical sites were completely healed. The bioadhesive gel resulted in a very promising agent for the post-operative management of oral biopsy site, without the need for surgical suture and chlorhexidine applications

    Gender and Psychosocial Differences in Psychological Resilience among a Community of Older Adults during the COVID-19 Pandemic

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    The study aimed at exploring gender and additional sociodemographic differences in psychological resilience, as well as the association between resilience and psychological distress in older adults, during the first lockdown in Italy, due to the COVID-19 pandemic. Participants attended an online survey during the first lockdown in May 2020. Psychological distress was assessed through the Depression Anxiety Stress Scale-21, the Resilience Scale (RS) was administered to evaluate psychological resilience, and sociodemographic variables were also collected. The study involved 108 community older adults (mean age 70.02 Âą 3.5 years). Comparisons revealed that women reported significantly lower total scores of RS (p = 0.027), as well as lower levels of resilience-related domains, namely Meaningfulness (p = 0.049), Self-Reliance (p = 0.011), Perseverance (p = 0.035), and Existential Aloneness (p = 0.014), compared to men. Significantly higher RS scores were found in older adults being involved in a relationship, compared to those not involved in relationships (p = 0.026), and in older adults with children (p = 0.015), compared to those without offspring, suggesting the importance for older adults of not dealing alone with such a dramatic and stressful event, such as the pandemic. Negative correlations were found between psychological resilience and stress, depression, and anxiety. Linear regressions revealed that lower RS total scores, as well as lower scores in the majority of the RS scales, were associated with greater levels of stress, greater levels of anxiety, and greater levels of depressive symptoms. This study suggested that older women might appear more vulnerable in facing the pandemic, compared to men; having not lived alone through the lockdown period might also be considered as a factor of resilience for older adults

    Actinomycosis of the Tongue: A Case Report and Review of Literature

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    Background: Actinomycosis of the tongue is an uncommon, suppurative infection of lingual mucosa, caused by actinomyces. The clinical diagnosis may present serious difficulties because of its ability to mimic other lesions, including both benign and malignant neoplasms. Methods: Here, we describe the case of a 52-years-old patient affected by an asymptomatic, tumor-like tongue swelling, then diagnosed as actinomycosis. A review of tongue localization of actinomycosis is also reported, with emphasis on clinical findings and therapy. Results and Conclusion: Early diagnosis and treatment, with pus drainage and systemic antibiotic therapy, are pivotal to avoid severe and life-threatening complications

    Efficacy of a functional therapy program for depression and c-reactive protein: A pilot study

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    Objective: Affecting more than 264 million people, depression is a systemic and multifactorial disorder that represents one of the leading causes of illness and disability worldwide. Several studies showed an inflammatory response in depressed patients, including the involvement of both chronic low-grade inflammatory response and activation of cell-mediated immunity. The present study aimed to verify the efficacy of a structured functional therapy program for patients with depressed mood, and to determine whether this program can significantly reduce levels of C-reactive protein. Method: 28 outpatients with depressed mood received 20 individual sessions of Functional therapy. Data about socio-demographic variables, depression, self-esteem, and quality of life were collected; moreover, blood specimens were collected before and after treatment, and CRP measurement was performed by immunoenzymatic method. All measures were administered at baseline, at the end of treatment (i.e., 3 months after baseline), and at follow‐up (i.e., 6 months after baseline). Results: A repeated measures ANOVA showed a significant difference after treatment on depression levels, levels of self‐esteem, and all dimensions of quality of life, such as physical, psychological, social relationships, and environment. Furthermore, a statistically significant difference on levels of CRP was found. Moreover, at follow‐up, improvements were maintained. Conclusions: The study revealed initial evidence of the efficacy of a functional therapy program on treating depression and its psychological and inflammation-related markers

    Benefits on coronary restenosis from elective paclitaxel-eluting stent implantation in patients aged 75 years and older

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    OBJECTIVE: Elderly patients are increasingly referred for revascularisation yet have been underrepresented in some large clinical trials. Although the advent of drug-eluting stents has dramatically reduced clinical events related to restenosis, older age remains one of the most important correlates of adverse outcome, even after an elective percutaneous coronary intervention (PCI). We sought to evaluate the impact of paclitaxel-eluting stents on coronary restenosis in elderly patients undergoing elective PCI. METHODS: Patients undergoing successful elective PCI with stenting of de novo coronary artery lesions were identified and screened for participation in this study. All patients included in our analysis were divided into two cohort groups: patients aged or=75 years (elderly cohort). We evaluated the six-month incidence of target lesion revascularisation (TLR) and major adverse cardiac events, which included TLR, death and myocardial infarction. RESULTS: A total of 171 (58 aged >or=75 years) consecutive patients were enrolled in the study. At six months, TLR rate was similar in both groups [1.77 vs. 1.72%, odds ratio (OR) 0.97, 95% confidence interval (CI) 0.08-10.9, P = 0.98, in the younger and elderly group, respectively]. Even the rate of major adverse cardiac events was comparable between the two groups (7.96 vs. 8.62%, OR 1.09, 95% CI 0.34-3.41, P = 0.88, in the younger and elderly group, respectively). Also the angiographic restenosis rates were comparable between patients or=75 years (4.42 vs. 3.46%, P = 0.76). CONCLUSIONS: After elective paclitaxel-eluting stent implantation, there is no difference in coronary restenosis in younger and elderly patients, suggesting an age-independent efficacy
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