1,033 research outputs found

    Evidence for a floating phase of the transverse ANNNI model at high frustration

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    We study the transverse quantum ANNNI model in the region of high frustration (k>0.5) using the DMRG algorithm. We obtain a precise determination of the phase diagram, showing clear evidence for the existence of a floating phase, separated from the paramagnetic modulated phase by a high-order critical line ending at the multicritical point. We obtain simple and accurate formulae for the two critical lines.Comment: 20 pages, 16 figures. Major revision: numerical evidence improved, presentation clarified, discussion on KT phase transitions added, references update

    Reporting di sostenibilità degli operatori logistici in Europa: analisi degli indicatori

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    Obiettivi: L’affermazione di una nuova concezione del valore, basata sulle qualità e non sull’insostenibile aumento delle quantità di merci e consumi, induce gli operatori logistici alla ricerca di azioni che possano essere nel contempo economicamente efficienti ed efficaci, ecologicamente sopportabili e socialmente giuste. Il presente lavoro ha l’obiettivo di investigare e identificare le azioni sostenibili - economiche, ambientali e sociali - intraprese dagli operatori logistici. Metodologia: Il quadro teorico è stato costruito attraverso lo studio della letteratura accademica nazionale e internazionale. La parte empirica è stata sviluppata attraverso l’analisi dei più recenti report di sostenibilità degli operatori logistici operanti in Europa, redatti secondo gli standard della Global Reporting Initiative. Risultati: Gli operatori logistici possono contribuire in modo significativo al cambiamento paradigmatico in atto, facilitando e favorendo, in qualità di fornitori di servizi, il raggiungimento della sostenibilità della supply chain. Limiti della ricerca: Il presente lavoro costituisce la fase preliminare di un più approfondito progetto di ricerca che indaghi le iniziative di sostenibilità degli operatori logistici a livello mondiale e che consideri un arco temporale di osservazione utile a tracciare il trend in atto. Implicazioni pratiche: Sia l’accademia che il mondo professionale possono trovare utile l’analisi della letteratura sul tema e i primi risultati ottenuti, in quanto sono posti in evidenzia i principali tratti di sostenibilità degli operatori logistici che già hanno intrapreso il percorso verso la sostenibilità. Originalità del lavoro: Gli studi della letteratura esistente sugli operatori logistici e la sostenibilità si basano quasi esclusivamente sulla sostenibilità ambientale e l’ecoefficienza, mentre manca un approccio sistemico capace di superare i problemi odierni mediante la valorizzazione della multidimensionalità. Il lavoro contribuisce a colmare questo gap

    Combination quetiapine therapy in the long-term treatment of patients with bipolar I disorder

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    OBJECTIVE: Determine the long-term effectiveness of quetiapine in combination with standard treatments in preventing relapses for patients with bipolar I disorders METHOD: Twenty-one outpatients with type I bipolar disorder who had inadequate responses to ongoing standard therapies were treated with add-on quetiapine in an open-label study. The quetiapine dose was increased until clinical response occurred. Illness response was assessed using the Clinical Global Impression (CGI) scale. Relapse rates before and during quetiapine treatment were compared by calculating incidence risk ratios. RESULTS: Quetiapine was added to ongoing standard therapy for 26 to 78 weeks. Thirteen patients received combination therapy for at least 52 weeks. The mean quetiapine dose received was 518 ± 244 mg/day. There were highly significant improvements in overall relapse rate, manic/mixed relapse rate, and depression relapse rate in the period during quetiapine treatment compared with the period before quetiapine was initiated. The calculated relative risk of relapse in the absence of quetiapine treatment was 2.9 overall (95% confidence interval, 1.5~5.6), 3.3 for manic/mixed relapse (95% confidence interval, 1.5~7.1), and 2.4 for depressive relapse (95% confidence interval, 1.3~4.4). The mean Clinical Global Impression scores improved significantly from baseline during 26 weeks of quetiapine treatment in 21 patients (p = 0.002) and remained significantly better during a 52-week treatment period in 13 patients (p = 0.036). CONCLUSION: Long-term treatment with quetiapine combination therapy reduced the probability of manic/mixed and depressive relapses and improved symptoms in patients with bipolar I disorder who had inadequate responses to ongoing standard treatment

    Horizontal network collaboration by entrepreneurial ventures: a supply chain finance perspective

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    Purpose – The present paper aims at understanding how horizontal network collaborations between small and medium enterprises (SMEs) can be designed and implemented to take advantage of a supply chain finance (SCF) perspective. Design/methodology/approach – This study presents an SCF literature background identifying four literature gaps, and in response to them it adopts an action research approach. The empirical analysis is developed on a network-case study: a horizontal collaboration project between small businesses of the Italian wine industry and their supply chains. Findings – SMEs can play an active role in developing – in terms of design and implementation – their collaborative networks by taking advantage of an SCF perspective for themselves, and their customers, based on the reorganization of relationships interface processes. Taking this perspective can be a concrete and crucial way to sustain the development of SMEs and their supply chains in an actual competitive context. Research limitations/implications – The paper identifies the theoretical gaps in the literature, suggests new research areas that deserve to be more deeply investigated and connects case-related results to the key concepts. The empirical part presents a real case application that proposes a complete roadmap for managers and practitioners who wish to experience similar projects. Practical implications – This network-case study storyline, presenting an overview of ten years of meetings, with related purposes, is suggesting a roadmap for design and implementation of horizontal network as managerial implications. These kinds of active research projects, with a collaborative mixed team of academics and practitioners, and involving a multilayer group of participants, are positive examples for closing the bridge between companies and academia, which enhance this network of small businesses active in trying to improve their competitiveness working together. Originality/value – The value of the paper is to embrace a supply chain-oriented perspective for an SME, independent of the financial system and based on inventory flow management. Very little literature focuses on inventory-based research within the SCF framework, designed for real implementation in horizontal network collaboration by entrepreneurial ventures

    Choroid plexus volume in multiple sclerosis can be estimated on structural MRI avoiding contrast injection

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    We compared choroid plexus (ChP) manual segmentation on non-contrast-enhanced (non-CE) sequences and reference standard CE T1- weighted (T1w) sequences in 61 multiple sclerosis patients prospectively included. ChP was separately segmented on T1w, T2-weighted (T2w) fluid-attenuated inversion-recovery (FLAIR), and CE-T1w sequences. Inter-rater variability assessed on 10 subjects showed high reproducibility between sequences measured by intraclass correlation coefficient (T1w 0.93, FLAIR 0.93, CE-T1w 0.99). CE-T1w showed higher signal-to-noise ratio and contrast-to-noise ratio (CE-T1w 23.77 and 18.49, T1w 13.73 and 7.44, FLAIR 13.09 and 10.77, respectively). Manual segmentation of ChP resulted 3.073 ± 0.563 mL (mean ± standard deviation) on T1w, 3.787 ± 0.679 mL on FLAIR, and 2.984 ± 0.506 mL on CE-T1w images, with an error of 28.02 ± 19.02% for FLAIR and 3.52 ± 12.61% for T1w. FLAIR overestimated ChP volume compared to CE-T1w (p < 0.001). The Dice similarity coefficient of CE-T1w versus T1w and FLAIR was 0.67 ± 0.05 and 0.68 ± 0.05, respectively. Spatial error distribution per slice was calculated after nonlinear coregistration to the standard MNI152 space and showed a heterogeneous profile along the ChP especially near the fornix and the hippocampus. Quantitative analyses suggest T1w as a surrogate of CE-T1w to estimate ChP volume.Relevance statement To estimate the ChP volume, CE-T1w can be replaced by non-CE T1w sequences because the error is acceptable, while FLAIR overestimates the ChP volume. This encourages the development of automatic tools for ChP segmentation, also improving the understanding of the role of the ChP volume in multiple sclerosis, promoting longitudinal studies.Key points • CE-T1w sequences are considered the reference standard for ChP manual segmentation.• FLAIR sequences showed a higher CNR than T1w sequences but overestimated the ChP volume.• Non-CE T1w sequences can be a surrogate of CE-T1w sequences for manual segmentation of ChP

    Multipotent Mesenchymal Stromal Stem Cell Expansion by Plating Whole Bone Marrow at a Low Cellular Density: A More Advantageous Method for Clinical Use

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    Mesenchymal stem cells (MSCs) are a promising source for cell therapy due to their pluripotency and immunomodulant proprieties. As the identification of “optimal” conditions is important to identify a standard procedure for clinical use. Percoll, Ficoll and whole bone marrow directly plated were tested from the same sample as separation methods. The cells were seeded at the following densities: 100 000, 10 000, 1000, 100, 10 cells/cm2. After reaching confluence, the cells were detached, pooled and re-plated at 1000, 500, 100, and 10 cells/cm2. Statistical analyses were performed. Cumulative Population Doublings (PD) did not show significant differences for the separation methods and seeding densities but only for the plating density. Some small quantity samples plated in T25 flasks at plating densities of 10 and 100 cells/cm2 did not produce any expansion. However, directly plated whole bone marrow resulted in a more advantageous method in terms of CFU-F number, cellular growth and minimal manipulation. No differences were observed in terms of gross morphology, differentiation potential or immunophenotype. These data suggest that plating whole bone marrow at a low cellular density may represent a good procedure for MSC expansion for clinical use

    Prenatal genetic counselling: issues and perspectives for pre-conceptional health care in Emilia Romagna (Northern Italy)

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    Background: there are many reasons why a couple may seek specialist genetic counselling about foetal risk. The referral for prenatal genetic counselling of women with a known risk factor during pregnancy has many disadvantages. Despite this, 10-20% of women seek counselling when already pregnant. Methods: data on 804 pregnant women out of 2 158 (37.3%) referred for genetic counselling in 2010 to three Clinical Genetic Services were retrospectively analysed. Patients referred only for advanced maternal age were analysed in a separate study. Results: the 804 pregnant women were referred for 932 counselling issues. 325 issues (34.9%) were identified during pregnancy and 607 (65.1%) were pre-existing. 81.2% of Italians compared to 41.8% of the non-Italians (P<0.01) had access to counselling before 13 weeks of gestation for risk factors present before pregnancy. An accurate genetic diagnosis was available in 25.0% of cases. In 21.7% of the cases an elevated a priori risk of >10% for the unborn child was established. Conclusions: genetic services provide 37.3% of counselling to pregnant women. Referral for genetic counselling during pregnancy can require considerable resources and pose significant ethical and organizational challenges. New models of pregnancy care in the community need to be developed. General practitioners and gynaecologists have an important role in the referral and in the defence of equity of access and a more structured approach to the participation of medical geneticists to primary practice should be considered

    A novel pathogenic BRCA1 splicing variant produces partial intron retention in the mature messenger RNA

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    About 10% of all breast cancers arise from hereditary mutations that increase the risk of breast and ovarian cancers; and about 25% of these are associated with the BRCA1 or BRCA2 genes. The identification of BRCA1/BRCA2 mutations can enable physicians to better tailor the clinical management of patients; and to initiate preventive measures in healthy carriers. The pathophysiological significance of newly identified variants poses challenges for genetic counseling. We characterized a new BRCA1 variant discovered in a breast cancer patient during BRCA1/2 screening by next-generation sequencing. Bioinformatic predictions; indicating that the variant is probably pathogenetic; were verified using retro-transcription of the patient's RNA followed by PCR amplifications performed on the resulting cDNA. The variant causes the loss of a canonic donor splice site at position +2 in BRCA1 intron 21; and consequently the partial retention of 156 bp of intron 21 in the patient's transcript; which demonstrates that this novel BRCA1 mutation plays a pathogenetic role in breast cancer. These findings enabled us to initiate appropriate counseling and to tailor the clinical management of this family. Lastly; these data reinforce the importance of studying the effects of sequence variants at the RNA level to verify their potential role in disease onset

    Enhancing identification and treatment of patients with concomitant chronic venous insufficiency and diabetes mellitus A modified Delphi study from the CODAC (ChrOnic venous disease and Diabetes Advisory Council) group

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    Background: Chronic venous insufficiency (CVI) and diabetes mellitus (DM) pose significant burdens to patients and healthcare systems. While the two diseases share a number of commonalities in risk factors and pathophysiology, they are often assessed and managed separately. This can lead to a worsening of comorbidities and limitations in a patient’s quality of life. This project aims to develop recommendations to enhance the identification and treatment of patients with concomitant CVI and DM. Methods: Using a modified Delphi method, a panel of experts developed 38 Likert Scale and two multiple choice questions across six key themes. These were used to form an online survey which was disseminated through a convenience sampling approach to CVI and DM healthcare professionals across Europe, Central America, South America, and the Middle East. The threshold for consensus was set at ≥75%.Results: A total of 238 responses were received. 27/38 statements attained &gt;90% agreement, nine of 38 attained between 75-90%, and two failed to meet the threshold (&lt;75%). The awareness around the impact of the two diseases was high, but a gap was highlighted in the identification of patients with concomitant CVI and DM. Conclusions: The high level of agreement shows that healthcare professionals are aware of the gaps in identification and treatment of patients with concomitant CVI and DM, and of the need to approach this as a combined therapy area. An algorithm is proposed to help the identification of at-risk patients and to provide recommendations on the management of patients with concomitant disease. (Cite this article as: Bozkurt AK, van Rijn MJ, Bouskela E, Gastaldi G, Glauser F, Haller H, et al. Enhancing identification and treatment of patients with concomitant chronic venous insufficiency and diabetes mellitus. A modified Delphi study from the CODAC (ChrOnic venous disease and Diabetes Advisory Council) group. Int Angiol 2023;42:427-35. DOI: 10.23736/S0392-9590.23.05061-7)</p
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