70 research outputs found
Hole-induced anomaly in the thermodynamic behavior of a one-dimensional Bose gas
We reveal an intriguing anomaly in the temperature dependence of the specific heat of a one-dimensional Bose gas. The observed peak holds for arbitrary interaction and remembers a superfluid-to-normal phase transition in higher dimensions, but phase transitions are not allowed in one dimension. The presence of the anomaly signals a region of unpopulated states which behaves as an energy gap and is located below the hole branch in the excitation spectrum. The anomaly temperature is found to be of the same order of the energy of the maximum of the hole branch. We rely on the Bethe Ansatz to obtain the specific heat exactly and provide interpretations of the analytically tractable limits. The dynamic structure factor is computed with the Path Integral Monte Carlo method for the first time. We notice that at temperatures similar to the anomaly threshold, the energy of the thermal fluctuations become comparable with the maximal hole energy, leading to a qualitative change in the structure of excitations. This excitation pattern experiences the breakdown of the quasi-particle description for any value of the interaction strength at the anomaly, similarly to any superfluid phase transition at the critical temperature. We provide indications for future observations and how the hole anomaly can be employed for in-situ thermometry, identifying different collisional regimes and understanding other anomalies in atomic, solid-state, electronic, spin-chain and ladder systems.Peer ReviewedPostprint (published version
Satisfaction with online teaching of medical statistics during the COVID-19 pandemic: A survey by the Education Committee of the Italian Society of Medical Statistics and Clinical Epidemiology
: On May 2020, after 2 months of online teaching with no face-to-face lectures, the Education Committee of the Italian scientific Society of Medical Statistics and Clinical Epidemiology conceived an online survey to assess satisfaction of Italian academics of medical statistics with online teaching and remote exams. This survey highlighted teachers' perceptions as well as opportunities and limitations of online teaching of medical statistics, biostatistics, and epidemiology. Although 61% of Italian academics of medical statistics declared to be favorable to provide online teaching of medical statistics, biostatistics, and epidemiology in the future, we recognize that distance education cannot substitute the unique value of teaching and knowledge exchange that could only be transmitted through a personal interaction between students and teachers. These indications may be useful to improve the quality of the teaching process in the future
Two new Malagasy species of genus Piper L. (Piperaceae): Piper malgassicum and Piper tsarasotrae and their phylogenetic position
Abdominal aorta angiosarcoma after endovascular aneurysm repair
Primary tumors originating within the wall of the arteries are rare and they frequently manifest late, making effective treatment a challenge. We describe here a case of Abdominal Aorta AngioSarcoma masqueraded as an infected EndoVascular Aortic Repair. The knowledge of this pathology from vascular surgeons and radiologist is crucial, because a prompt diagnosis and treatment can improve the prognosis
Case Report: First Report of Fatal Legionella pneumophila and Klebsiella pneumoniae Coinfection in a Kidney Transplant Recipient
A very rare case of pulmonary Klebsiella pneumoniae-Legionella pneumophila coinfection in a double kidney transplanted man affected by the chronic renal disease is described.
Cases of Legionnaires’ disease with an incubation period of 14 days have rarely been documented. Despite the long period of hospitalization, typing of clinical and environmental L. pneumophila strains demonstrated that the patient’s home water distribution system was the source of infection, highlighting that Legionella house contamination can be a hidden risk, especially for immune-compromised people
Acute arterial and deep venous thromboembolism in COVID-19 patients. Risk factors and personalized therapy
The Lombardy region suffered severely during the acute phase of the coronavirus diease 2019 outbreak in Italy (Mar-Apr 2020) with 16,000 diagnosed coronavirus disease 2019-related deaths (49% of the total coronavirus disease 2019-related deaths in Italy). In the area surrounding Pavia during the critical stage of the outbreak (Mar-Apr 2020), 1,225 of the documented 4,200 deaths were related to coronavirus disease 2019 infection, with a mortality rate of 181/100,000 inhabitants and an increase in deaths of 138% compared with the same period during previous years. Our aim was to report the experience of the Department of Vascular Surgery of Pavia (Lombardy, Italy), including the lessons learned and future perspectives regarding the management of coronavirus disease 2019 patients who developed severe acute ischemia with impending lower limb loss or deep vein thrombosis
Improvement of Legionnaires' disease diagnosis using real-time PCR assay: a retrospective analysis, Italy, 2010 to 2015
AimTo evaluate real-time PCR as a diagnostic method for Legionnaires' disease (LD). Detection of Legionella DNA is among the laboratory criteria of a probable LD case, according to the European Centre for Disease Prevention and Control, although the utility and advantages, as compared to culture, are widely recognised.MethodsTwo independent laboratories, one using an in-house and the other a commercial real-time PCR assay, analysed 354 respiratory samples from 311 patients hospitalised with pneumonia between 2010-15. The real-time PCR reliability was compared with that of culture and urinary antigen tests (UAT). Concordance, specificity, sensitivity and positive and negative predictive values (PPV and NPV, respectively) were calculated.ResultsOverall PCR detected eight additional LD cases, six of which were due to Legionella pneumophila (Lp) non-serogroup 1. The two real-time PCR assays were concordant in 99.4% of the samples. Considering in-house real-time PCR as the reference method, specificity of culture and UAT was 100% and 97.9% (95% CI: 96.2-99.6), while the sensitivity was 63.6% (95%CI: 58.6-68.6) and 77.8% (95% CI: 72.9-82.7). PPV and NPV for culture were 100% and 93.7% (95% CI: 91.2-96.3). PPV and NPV for UAT were 87.5% (95% CI: 83.6-91.4) and 95.8% (95% CI: 93.5-98.2).ConclusionRegardless of the real-time PCR assay used, it was possible to diagnose LD cases with higher sensitivity than using culture or UAT. These data encourage the adoption of PCR as routine laboratory testing to diagnose LD and such methods should be eligible to define a confirmed LD case
Recommended from our members
A Knowledge Brokering Framework for Integrated Landscape Management
Sustainable land management is at the heart of some of the most intractable challenges facing humanity in the 21st century. It is critical for tackling biodiversity loss, land degradation, climate change and the decline of ecosystem services. It underpins food production, livelihoods, dietary health, social equity, climate change adaptation, and many other outcomes. However, interdependencies, trade-offs, time lags, and non-linear responses make it difficult to predict the combined effects of land management decisions. Policy decisions also have to be made in the context of conflicting interests, values and power dynamics of those living on the land and those affected by the consequences of land use decisions. This makes designing and coordinating effective land management policies and programmes highly challenging. The difficulty is exacerbated by the scarcity of reliable data on the impacts of land management on the environment and livelihoods. This poses a challenge for policymakers and practitioners in governments, development banks, non-governmental organisations, and other institutions. It also sets demands for researchers, who are under ever increasing pressure from funders to demonstrate uptake and impact of their work. Relatively few research methods exist that can address such questions in a holistic way. Decision makers and researchers need to work together to help untangle, contextualise and interpret fragmented evidence through systems approaches to make decisions in spite of uncertainty. Individuals and institutions acting as knowledge brokers can support these interactions by facilitating the co-creation and use of scientific and other knowledge. Given the patchy nature of data and evidence, particularly in developing countries, it is important to draw on the full range of available models, tools and evidence. In this paper we review the use of evidence to inform multiple-objective integrated landscape management policies and programmes, focusing on how to simultaneously achieve different sustainable development objectives in diverse landscapes. We set out key success factors for evidence-based decision-making, which are summarised into 10 key principles for integrated landscape management knowledge brokering in integrated landscape management and 12 key skills for knowledge brokers. We finally propose a decision-support framework to organise evidence that can be used to tackle different types of land management policy decision
Toxic properties of microsome-associated alpha-synuclein species in mouse primary neurons
α-synuclein (αS) is a small protein that self-aggregates into α-helical oligomer species and subsequently into larger insoluble amyloid fibrils that accumulate in intraneuronal inclusions during the development of Parkinson's disease. Toxicity of αS oligomers and fibrils has been long debated and more recent data are suggesting that both species can induce neurodegeneration. However while most of these data are based on differences in structure between oligomer and aggregates, often preassembled in vitro, the in vivo situation might be more complex and subcellular locations where αS species accumulate, rather than their conformation, might contribute to enhanced toxicity. In line with this observation, we have shown that αS oligomers and aggregates are associated with the endoplasmic reticulum/microsomes (ER/M) membrane in vivo and how accumulation of soluble αS oligomers at the ER/M level precedes neuronal degeneration in a mouse model of α-synucleinopathies. In this paper we took a further step, investigating the biochemical and functional features of αS species associated with the ER/M membrane. We found that by comparison with non-microsomal associated αS (P10), the ER/M-associated αS pool is a unique population of oligomers and aggregates with specific biochemical traits such as increased aggregation, N- and C-terminal truncations and phosphorylation at serine 129. Moreover, when administered to murine primary neurons, ER/M-associated αS species isolated from diseased A53T human αS transgenic mice induced neuronal changes in a time- and dose-dependent manner. In fact the addition of small amounts of ER/M-associated αS species from diseased mice to primary cultures induced the formation of beads-like structures or strings of fibrous αS aggregates along the neurites, occasionally covering the entire process or localizing at the soma level. By comparison treatment with P10 fractions from the same diseased mice resulted in the formation of scarce and small puncta only when administered at high amount. Moreover, increasing the amount of P100/M fractions obtained from diseased and, more surprisingly, from presymptomatic mice induced a significant level of neuronal death that was prevented when neurons were treated with ER/M fractions immunodepleted of αS high molecular weight (HMW) species. These data provide the first evidence of the existence of two different populations of αS HMW species in vivo, putting the spotlight on the association to ER/M membrane as a necessary step for the acquisition of αS toxic features
- …