17 research outputs found
Real-space many-body marker for correlated Z2 topological insulators
Taking the clue from the modern theory of polarization [Rev. Mod. Phys. 66, 899 (1994)], we identify an operator to distinguish between Z2-even (trivial) and Z2-odd (topological) insulators in two spatial dimen- sions. Its definition extends the position operator [Phys. Rev. Lett. 82, 370 (1999)], which was introduced in one-dimensional systems. We first show a few examples of noninteracting models where single-particle wave functions are defined and allow for a direct comparison with standard techniques on large system sizes. Then, we illustrate its applicability for an interacting model on a small cluster where exact diagonalizations are available. Its formulation in the Fock space allows a direct computation of expectation values over the ground-state wave function (or any approximation of it), thus, allowing us to investigate generic interacting systems, such as strongly correlated topological insulators
The Exploration and Practice of Party Member of College Students rdquo;Recognizing Position and Taking Responsibility for a Model”
AbstractNowadays, it has become more important to strengthen the education, management and training work of the party members of college students. Our school has carried out the party members of college students. rdquo;recognizing position and taking responsibility for a model” activity for two years. And obtained some experience. The party members of college students rdquo;recognizing position and taking responsibility for a model” activity should set up scientific positions, define their responsibilities clearly and strengthen the management and assessment
Development and implementation of a stroke rehabilitation integrated care pathway in an Italian no profit institution: an observational study
Covid-19 and the role of smoking: the protocol of the multicentric prospective study COSMO-IT (COvid19 and SMOking in ITaly).
The emergency caused by Covid-19 pandemic raised interest in studying lifestyles and comorbidities as important determinants of poor Covid-19 prognosis. Data on tobacco smoking, alcohol consumption and obesity are still limited, while no data are available on the role of e-cigarettes and heated tobacco products (HTP). To clarify the role of tobacco smoking and other lifestyle habits on COVID-19 severity and progression, we designed a longitudinal observational study titled COvid19 and SMOking in ITaly (COSMO-IT). About 30 Italian hospitals in North, Centre and South of Italy joined the study. Its main aims are: 1) to quantify the role of tobacco smoking and smoking cessation on the severity and progression of COVID-19 in hospitalized patients; 2) to compare smoking prevalence and severity of the disease in relation to smoking in hospitalized COVID-19 patients versus patients treated at home; 3) to quantify the association between other lifestyle factors, such as e-cigarette and HTP use, alcohol and obesity and the risk of unfavourable COVID-19 outcomes. Socio-demographic, lifestyle and medical history information will be gathered for around 3000 hospitalized and 700-1000 home-isolated, laboratory-confirmed, COVID-19 patients. Given the current absence of a vaccine against SARS-COV-2 and the lack of a specific treatment for -COVID-19, prevention strategies are of extreme importance. This project, designed to highly contribute to the international scientific debate on the role of avoidable lifestyle habits on COVID-19 severity, will provide valuable epidemiological data in order to support important recommendations to prevent COVID-19 incidence, progression and mortality
Voxelwise encoding models of body stimuli reveal a representational gradient from low-level visual features to postural features in occipitotemporal cortex
Voxelwise encoding models of body stimuli reveal a representational gradient from low-level visual features to postural features in occipitotemporal cortex
Research on body representation in the brain has focused on category-specific representation, using fMRI to investigate the response pattern to body stimuli in occipitotemporal cortex without so far addressing the issue of the specific computations involved in body selective regions, only defined by higher order category selectivity. This study used ultra-high field fMRI and banded ridge regression to investigate the coding of body images, by comparing the performance of three encoding models in predicting brain activity in occipitotemporal cortex and specifically the extrastriate body area (EBA). Our results suggest that bodies are encoded in occipitotemporal cortex and in the EBA according to a combination of low-level visual features and postural features
Davunetide (NAP) Protects the Retina Against Early Diabetic Injury by Reducing Apoptotic Death
© 2014, Springer Science+Business Media New York. Davunetide (NAP) is an eight amino acid peptide that has been shown to provide potent neuroprotection. In the present study, we investigated the neuroprotective effect of NAP in diabetic retinopathy using an in vivo streptozotocin (STZ)-induced diabetic model. A single intraocular injection of NAP (100 μg/mL) or vehicle was administered 1 week after STZ injection. Three weeks after diabetes induction, we assessed the retinal expression and distribution of apoptosis markers, cleaved caspase-3, and Bcl2, by Western blot and immunofluorescent analysis. Furthermore, we evaluated the activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/ERK) and/or phosphatidylinositol-3 kinase/Akt pathways by measuring the protein levels of p-ERK and p-AKT with or without NAP treatment. Results demonstrated that NAP treatment reduced apoptotic event in diabetic retina, and it restored cleaved caspase-3 expression levels in the retina of STZ-injected rats as well as the decreased Bcl2. NAP treatment improved cellular survival through the activation of the MAPK/ERK pathway. Taken together, these findings suggested that NAP might be useful to treat retinal degenerative diseases
Late reopening of an occluded infarct related artery improves left ventricular function and long term clinical outcome.
OBJECTIVE:
To assess effects on left ventricular (LV) function and on long term clinical outcome of late percutaneous transluminal coronary angioplasty (PTCA) of a chronically occluded infarct related artery.
METHODS:
65 patients who underwent PTCA a mean (SD) of 6.0 (1.2) months after a previous myocardial infarction were divided in two groups according to dilated artery patency status after PTCA: group 1 (35 patients with TIMI (thrombolysis in myocardial infarction) grade 3 flow) and group 2 (30 patients with TIMI grade 0-2 flow). Echocardiography was performed at admission and at six months' follow up. A three year follow up was conducted with major adverse cardiac events (MACE) as end points.
RESULTS:
At follow up, group 1 had improved global LV ejection fraction (48.7% v 43.6%, p < 0.001) and LV indexed end diastolic and end systolic volumes (75 v 86 ml/m(2) and 40 v 53 ml/m(2), respectively, p = 0.011) compared with group 2. Kaplan-Meier analysis showed a higher incidence of cardiac death (p = 0.02) and MACE (p < 0.0001) in group 2. TIMI 3 after PTCA was an independent predictor of event-free survival at follow up.
CONCLUSION:
Late PTCA of a chronically occluded infarct related artery improves LV function, reduces cardiac death, and improves long term clinical outcome
Relationship between contractile reserve, Tl-201 uptake, and collateral angiographic circulation in collateral-dependentmyocardium: implications regarding the evaluation of myocardial viability.
BACKGROUND:
The aim of this study was to compare collateral angiographic circulation (CC), thallium 201 single photon emission computed tomography (SPECT), low-dose dobutamine echocardiography (LDDE), and their combination in identifying viable myocardium beyond a chronic occlusion.
METHODS AND RESULTS:
We studied 33 consecutive patients with a chronic occluded coronary artery and regional ventricular dysfunction who underwent dobutamine infusion (5-10 microg x kg(-1) x min(-1)), Tl-201 SPECT, and coronary revascularization (15 patients underwent coronary artery bypass grafting and 18 patients percutaneous transluminal coronary angioplasty). Echocardiography and Tl-201 SPECT at rest were repeated 90 +/- 48 days after revascularization. For viability assessment, Tl-201 SPECT showed the best sensitivity and accuracy (77% and 72%, respectively) compared with LDDE (64% and 63%, respectively) and CC (74% and 55%, P < .05 vs Tl-201 SPECT). Specificity was significantly better for both Tl-201 SPECT (65%) and LDDE (62%) compared with collateral circulation (27%, P < .001 vs Tl-201 SPECT and LDDE). Furthermore, combined Tl-201 SPECT and LDDE data improved specificity (from 88% to 92%) and positive predictive power (from 75% to 78%) but not global accuracy. A direct relationship between the number of viable segments and global functional recovery after revascularization was found only in the case of Tl-201 SPECT (r = 0.48, P = .04).
CONCLUSIONS:
This study demonstrates that CC has a very low specificity in the evaluation of viability in collateral-dependent myocardium and that LDDE has a very low sensitivity, whereas Tl-201 SPECT is the most reliable method, particularly in akinetic segments, and optimally identifies patients who will mostly benefit from revascularization in terms of ventricular functional improvement. No additional advantages in terms of accuracy were found when Tl-201 SPECT and LDDE data were combined
Diagnosis and Clinical Management of Neuroendocrine Tumor of the Breast: Report of Six Cases and Systematic Review of Existing Literature
ntroduction: Neuroendocrine neoplasm of the breast (bNENs) are considered a rare disease, even if in WHO data they represent about 2-5 % of all breast cancer. The last WHO classification includes: well-differentiated neuroendocrine tumor (bNET), neuroendocrine carcinoma (NEC) and invasive carcinoma with neuroendocrine differentiation. The current knowledge on clinical management of bNENs is poor and patients are usually treated according to non-endocrine tumor components guidelines.
Materials and Methods: We presented our experience of six cases of bNENs. Moreover, we conducted a systematic review of published data on diagnosis, treatment and outcome of this kind of tumors.
Results: bNENS usually presented as palpable breast masses, classically appearing as irregular hypoechoic lesions at US examination and as hyperdense masses at mammography. Usually pre-operative tumor biopsy is not able to recognize the neuroendocrine components and the final diagnosis is performed only on definitive histopathological assessment. The most frequent subtype seems to be neuroendocrine carcinoma and synaptophysin is positive in most specimens. Treatment strategies, including surgical treatment, radiotherapy and medical treatment are nowadays based on current non-endocrine breast cancer guidelines, independently from neuroendocrine components, even if some studies have proposed the use of somatostatin analogues for bNET and cisplatin-etoposide for NEC. Prognosis of all bNENs, especially of poorly differentiated neoplasia, seems worse compared to non-neuroendocrine breast cancer and stage and morphology seem the best predictor of tumor outcome.
Conclusions: We provide an algorithm for clinical management of bNETs, basing on available data. More studies are necessary for confirming the best treatment strategy for these patients, in order to improve clinical outcome