Tracking-ADMM for Distributed Constraint-Coupled Optimization

We consider constraint-coupled optimization problems in which agents of a network aim to cooperatively minimize the sum of local objective functions subject to individual constraints and a common linear coupling constraint. We propose a novel optimization algorithm that embeds a dynamic average consensus protocol in the parallel Alternating Direction Method of Multipliers (ADMM) to design a fully distributed scheme for the considered set-up. The dynamic average mechanism allows agents to track the time-varying coupling constraint violation (at the current solution estimates). The tracked version of the constraint violation is then used to update local dual variables in a consensus-based scheme mimicking a parallel ADMM step. Under convexity, we prove that all limit points of the agents' primal solution estimates form an optimal solution of the constraint-coupled (primal) problem. The result is proved by means of a Lyapunov-based analysis simultaneously showing consensus of the dual estimates to a dual optimal solution, convergence of the tracking scheme and asymptotic optimality of primal iterates. A numerical study on optimal charging schedule of plug-in electric vehicles corroborates the theoretical results.Comment: 14 pages, 2 figures, submitted to Automatic

Prevalence of methicillin-resistant staphylococci isolated from different biological samples at Policlinico Umberto I of Rome: correlation with vancomycin susceptibility

The methicillin-resistance is increasing all over the world in the last decade. It is more frequent among coagulase-negative staphylococci (MRCoNS); infact the 52% of S. epidermidis strains results to be resistant to methicillin.The methicillin-resistant strains also show a reduced sensitivity towards the first-line agents such as glycopeptides and other antibiotics commonly used in therapy such as trimethoprim-sulphamethoxazole, imipenem, gentamycin, fosfomycin and chlarytromicin. Unlike MRSA (Methicillin-resistant S. aureus), MRCoNS resistance to glycopeptides generally concerns teicoplanin. Although vancomycin resistance is rare in Staphylococcus isolates, the detected shift towards higher values of MICs might affect patient's clinical outcome

Inhibitory effect of vitamin K1 on growth and polyamine biosynthesis of human gastric and colon carcinoma cell lines

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Homogeneous Floquet time crystal protected by gauge invariance

We show that homogeneous lattice gauge theories can realize nonequilibrium quantum phases with long-range spatiotemporal order protected by gauge invariance instead of disorder. We study a kicked $\mathbb{Z}_2$-Higgs gauge theory and find that it breaks the discrete temporal symmetry by a period doubling. In a limit solvable by Jordan-Wigner analysis we extensively study the time-crystal properties for large systems and further find that the spatiotemporal order is robust under the addition of a solvability-breaking perturbation preserving the $\mathbb{Z}_2$ gauge symmetry. The protecting mechanism for the nonequilibrium order relies on the Hilbert space structure of lattice gauge theories, so that our results can be directly extended to other models with discrete gauge symmetries.Comment: 6 pages and 4 figures + 3 pages and 3 figures of Supplementary Informatio

Comparison of pain perception between open and minimally invasive surgery in total knee arthroplasty

Total knee arthroplasty (TKA) was a well-established procedure that had shown excellent long-term results in terms of reduced pain and increased mobility. Pain was one of the most important outcome measures that contributed to patient dissatisfaction after TKA. After a computerized search of the Medline and Embase databases, we considered articles from January 1st, 1997 to October 31st, 2009 that underlined the impact on patient pain perception of either standard open total knee arthroplasty or minimally invasive total knee arthroplasty. We included articles that used the visual analog scale (VAS), Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC), Knee Score, Hospital for Special Surgery Score (HSS), Oxford Knee Score (OKS) as postoperative pain indicators, and we included studies with a minimum follow-up period of two months. We excluded studies that monitored only functional postoperative knee activities. It was shown that TKA with the open technique was a better treatment for knees with a positive effect on pain and function than the minimally invasive technique

The role of life cycle assessment in supporting sustainable agri-food systems: A review of the challenges

Life cycle thinking is increasingly seen as a key concept for ensuring a transition towards more sustainable production and consumption patterns. As food production systems and consumption patterns are among the leading drivers of impacts on the environment, it is important to assess and improve foodrelated supply chains as much as possible. Over the years, life cycle assessment has been used extensively to assess agricultural systems and food processing and manufacturing activities, and compare alternatives “from field to fork” and through to food waste management. Notwithstanding the efforts, several methodological aspects of life cycle assessment still need further improvement in order to ensure adequate and robust support for decision making in both business and policy development contexts. This paper discusses the challenges for life cycle assessment arising from the complexity of food systems, and recommends research priorities for both scientific development and improvements in practical implementation. In summary, the intrinsic variability of food production systems requires dedicated modelling approaches, including addressing issues related to: the distinction between technosphere and ecosphere; the most appropriate functional unit; the multi-functionality of biological systems; and the modelling of the emissions and how this links with life cycle impact assessment. Also, data availability and interpretation of the results are two issues requiring further attention, including how to account for consumer behaviour.info:eu-repo/semantics/publishedVersio

In quest of reducing the environmental impacts of food production and consumption

Food supply chains are increasingly associated with environmental and socio-economic impacts. An increasing global population, an evolution in consumers' needs, and changes in consumption models pose serious challenges to the overall sustainability of food production and consumption. Life cycle thinking (LCT) and assessment (LCA) are key elements in identifying more sustainable solutions for global food challenges. In defining solutions to major global challenges, it is fundamentally important to avoid burden shifting amongst supply chain stages and amongst typologies of impacts, and LCA should, therefore, be regarded as a reference method for the assessment of agri-food supply chains. Hence, this special volume has been prepared to present the role of life cycle thinking and life cycle assessment in: i) the identification of hotspots of impacts along food supply chains with a focus on major global challenges; ii) food supply chain optimisation (e.g. productivity increase, food loss reduction, etc.) that delivers sustainable solutions; and iii) assessment of future scenarios arising from both technological improvements and behavioural changes, and under different environmental conditions (e.g. climate change). This special volume consists of a collection of papers from a conference organized within the last Universal Exposition (EXPO2015) “LCA for Feeding the planet and energy for life” in Milan (Italy) in 2015 as well as other contributions that were submitted in the year after the conference that addressed the same key challenges presented at the conference. The papers in the special volume address some of the key challenges for optimizing food-related supply chains by using LCA as a reference method for environmental impact assessment. Beyond specific methodological improvements to better tailor LCA studies to food systems, there is a clear need for the LCA community to “think outside the box”, exploring complementarity with other methods and domains. The concepts and the case studies presented in this special volume demonstrate how cross-fertilization among difference science domains (such as envi- ronmental, technological, social and economic ones) may be key elements of a sustainable “today and tomorrow” for feeding the planet.info:eu-repo/semantics/publishedVersio

Health-related quality of life and working conditions among nursing providers

OBJETIVO: Avaliar condições de trabalho associadas à qualidade de vida relacionada à saúde entre profissionais de enfermagem. MÉTODOS: Estudo transversal realizado em um hospital universitário de São Paulo, SP, em 2004-2005. A população estudada foi de 696 enfermeiros, técnicos e auxiliares de enfermagem, predominantemente feminina (87,8 por cento) e que trabalhava em turnos diurnos e/ou noturnos. Os dados sociodemográficos, de condições de trabalho e de vida, hábitos de vida e sintomas de saúde auto-referidos foram obtidos por meio de questionários auto-aplicados: Resultados de Estudos de Saúde - versão reduzida, Escala de Estresse no Trabalho e Desequilíbrio Esforço-Recompensa. Valores do coeficiente 1,01 significam mais esforços do que recompensas no trabalho. Modelos de regressão logística ordinal de chances proporcionais foram ajustados para cada dimensão do SF-36. RESULTADOS: Aproximadamente 22 por cento da população foi classificada como trabalhando em condições de alto desgaste e 8 por cento com mais esforços do que recompensas no trabalho. As dimensões com piores escores médios no SF-36 foram vitalidade, dor e saúde mental. Alto desgaste no trabalho, ter mais esforços que recompensas e ser enfermeira associaram-se de maneira independente aos baixos escores da dimensão de aspectos emocionais. As dimensões relacionadas à saúde mental foram as que mais sofreram influência dos fatores psicossociais do trabalho. CONCLUSÕES: Apresentar mais esforços do que recompensas no trabalho foi mais significativo para a qualidade de vida associada à saúde do que o alto desgaste no trabalho (altas demandas e baixo controle). Os resultados indicam que a análise conjunta dos fatores psicossociais de desequilíbrio esforço-recompensa e demanda-controle contribuiu para a discussão sobre os papéis profissionais, condições de trabalho e qualidade de vida relacionada à saúde de profissionais de enfermagemOBJECTIVE: To evaluate working conditions associated with health-related quality of life (HRQL) among nursing providers. METHODS: Cross-sectional study conducted in a university hospital in the city of São Paulo, Southeastern Brazil, during 2004-2005. The study sample comprised 696 registered nurses, nurse technicians and nurse assistants, predominantly females (87.8%), who worked day and/or night shifts. Data on sociodemographic information, working and living conditions, lifestyles, and health symptoms were collected using self-administered questionnaires. The following questionnaires were also used: Job Stress Scale, Effort-Reward Imbalance (ERI) and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Ordinal logistic regression analysis using proportional odds model was performed to evaluate each dimension of the SF-36. RESULTS: Around 22% of the sample was found to be have high strain and 8% showed an effort-reward imbalance at work. The dimensions with the lowest mean scores in the SF-36 were vitality, bodily pain and mental health. High-strain job, effort-reward imbalance (ERI>1.01), and being a registered nurse were independently associated with low scores on the role emotional dimension. Those dimensions associated to mental health were the ones most affected by psychosocial factors at work. CONCLUSIONS: Effort-reward imbalance was more associated with health than high-strain (high demand and low control). The study results suggest that the joint analysis of psychosocial factors at work such as effort-reward imbalance and demand-control can provide more insight to the discussion of professional roles, working conditions and HRQL of nursing provider