Waste heat to power conversion by means of thermomagnetic hydrodynamic energy harvester

Energy harvesting from extremely low enthalpy sources can play an important role in increasing the sustainability of future energy applications: low temperature differences are common and offer an abundant source, available both in the natural environment and as the result of a many industrial process. This paper presents the first closed-loop thermomagnetic hydrodynamic energy harvester, based on thermomagnetic advection and exploiting a commercial ferrofluid. The lab-scale prototype has a toroidal geometry adopted from the well-known tokamak inertial machines. Peltier modules are used to control the thermal gradient that is harvested and converted directly to electric energy, while permanent magnets trigger the advection. Temperature sensors are installed along the toroidal walls (thermistors) and are placed in contact with the rotating fluid (thermocouples). To extract and ensure the electrical energy output, the structure is wrapped-up with induction coils. Two coil configurations (purely poloidal and mixed poloidal/toroidal windings) are tested, in a heterogeneous two-phase flow from the combination of water carrier and ferrofluid packets, reaching a maximum extracted electrical power per unit of temperature difference of 10.4 μW/K. This positions the device close to 20% of the ideal Carnot efficiency of a thermal machine working on the same temperature drop. Numerical analysis of the system has been performed developing a Fortran™ code in a Eulerian framework, using a mixed Fourier-Galerkin/finite difference spatial discretization. The harvester is suitable for producing electricity from running engines, appliances, warm gas exhausts, exothermic processes

The experience of individuals placed in quarantine: A systematic review, meta-summary, and meta-synthesis

Objective: To summarize the experience of individuals placed in quarantine during an outbreak. Design: A meta-summary and a meta-synthesis based upon a systematic review of qualitative studies. Sample: The Cumulative Index of Nursing and Allied Health Literature, MEDLINE, and Scopus databases were all searched up to April 2020. Measurements: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed; then, the methodological quality of the studies included was assessed with the Critical Appraisal Screening Programme tool for qualitative studies. Results: Five studies have been included documenting the experience of 125 adult individuals. A total of 16 codes emerged: in the meta-summary, the most and least frequent codes were \u201cThinking about quarantine\u201d (80%) and \u201cEmotional roller coaster,\u201d \u201cBeing alert for any symptom,\u201d \u201cTrusting or not?,\u201d \u201cKnowing who brought the infection,\u201d and \u201cLiving in a surreal world\u201d (20%). The codes which emerged were categorized into three main themes which summarized the whole experience of being placed in quarantine: (a) \u201cBeing swamped with a thousand emotions\u201d; (b) \u201cBeing restrained\u201d; and (c) \u201cNeeding to be considered.\u201d. Conclusions: The experience of quarantine for people is a long journey which can feel chaotic due to uncertainty about the consequences on health, work, and the future. The findings of this study can help nurses in caring for quarantined individuals by enabling them to understand people's need for educational and emotional support. Ensuring the supply of consistent information is also important to increase people's compliance

Open-ended evolution to discover analogue circuits for beyond conventional applications

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10710-012-9163-8. Copyright @ Springer 2012.Analogue circuits synthesised by means of open-ended evolutionary algorithms often have unconventional designs. However, these circuits are typically highly compact, and the general nature of the evolutionary search methodology allows such designs to be used in many applications. Previous work on the evolutionary design of analogue circuits has focused on circuits that lie well within analogue application domain. In contrast, our paper considers the evolution of analogue circuits that are usually synthesised in digital logic. We have developed four computational circuits, two voltage distributor circuits and a time interval metre circuit. The approach, despite its simplicity, succeeds over the design tasks owing to the employment of substructure reuse and incremental evolution. Our findings expand the range of applications that are considered suitable for evolutionary electronics

Homeodomain Interacting Protein Kinase 2 Activation Compromises Endothelial Cell Response to Laminar Flow: Protective Role of p21waf1,cip1,sdi1

BACKGROUND: In the cardiovascular system, laminar shear stress (SS) is one of the most important source of endothelial protecting signals. Physical and chemical agents, however, including ionising radiations and anticancer drugs, may injure endothelial cells determining an increase in oxidative stress and genotoxic damage. Whether the SS protective function remains intact in the presence of strong oxidants or DNA damage is currently unclear. METHODS AND RESULTS: To investigate this aspect a series of experiments were performed in which HUVEC were exposed to sub-lethal doses of the radio-mimetic compound Bleomycin (Bleo; 10 microg/ml) which generated free radicals (ROS) without significantly compromising cell survival. Remarkably, the application of a SS of 12 dyne/cm(2) did not protect endothelial cells but markedly accelerated apoptosis compared to controls kept in static culture and in the presence of Bleo. Experiments with the inducible nitric oxide synthase (iNOS) inhibitor GW274150 significantly reduced the SS-dependent apoptosis indicating that the production of NO was relevant for this effect. At molecular level, the ataxia-telangectasia-mutated (ATM) kinase, the homeodomain-interacting protein kinase-2 (HIPK2) and p53 were found activated along a pro-apoptotic signalling pathway while p21(waf1,cip1,sdi1) was prevented from its protective action. RNA interference experiments revealed that HIPK2 and p53 were both important for this process, however, only the forced expression p21(waf1,cip1,sdi1) fully restored the SS-dependent pro-survival function. CONCLUSIONS: This study provides the first evidence that, in the presence of genotoxic damage, laminar flow contributes to endothelial toxicity and death and identifies molecular targets potentially relevant in endothelial dysfunction and cardiovascular disease pathogenesis

Effect of vitamin D on muscle function and injury in elite adolescent dancers: A randomized double-blind study

A number of studies have noted low levels of Vitamin D in dancers and this has been associated with increased risk of injuries and decreased muscular strength indices. The aim of the present study was to examine whether vitamin D supplementation over a 4-month period can improve muscle function and injury incidence. Eighty-four participants volunteered, exclusion criteria and drop out (19%) reduced cohort to 67 (f=29, m=38; 17-19yrs). Participants were randomly assigned to either an intervention or placebo group (2:1 ratio). All provided a venous blood sample pre and post the 4-month study period. The intervention group received 120,000IU vitamin D to be taken over a 1-week period and the placebo group received the same number of inert pills. Participants completed a series of muscle function tests pre and post the monitoring period. Injury incidence was recorded by the independent health team at the school. Pre-intervention 6% of the cohort were vitamin D deficient, 81% were insufficient and 13% had sufficient levels; post-intervention 53% were insufficient and 47% were sufficient. The intervention group reported a significant increase in serum 25(OH)D3 (57%; p<0.00) and isometric strength (7.8%; p=0.022) but not muscular power. There was a significant association between traumatic injury occurrence for the intervention and control groups (10.9% vs. 31.8%; p < .02). Vitamin D supplementation decreased the numbers of deficient and insufficient participants within this cohort. The intervention group reported a small significant increase in muscle strength that was negatively associated with traumatic injury occurrence

On morphological hierarchical representations for image processing and spatial data clustering

Hierarchical data representations in the context of classi cation and data clustering were put forward during the fties. Recently, hierarchical image representations have gained renewed interest for segmentation purposes. In this paper, we briefly survey fundamental results on hierarchical clustering and then detail recent paradigms developed for the hierarchical representation of images in the framework of mathematical morphology: constrained connectivity and ultrametric watersheds. Constrained connectivity can be viewed as a way to constrain an initial hierarchy in such a way that a set of desired constraints are satis ed. The framework of ultrametric watersheds provides a generic scheme for computing any hierarchical connected clustering, in particular when such a hierarchy is constrained. The suitability of this framework for solving practical problems is illustrated with applications in remote sensing

Synthetic microparticles conjugated with VEGF165 improve the survival of endothelial progenitor cells via microRNA-17 inhibition

Several cell-based therapies are under pre-clinical and clinical evaluation for the treatment of ischemic diseases. Poor survival and vascular engraftment rates of transplanted cells force them to work mainly via time-limited paracrine actions. Although several approaches, including the use of soluble vascular endothelial growth factor (sVEGF)-VEGF165, have been developed in the last 10 years to enhance cell survival, they showed limited efficacy. Here, we report a pro-survival approach based on VEGF-immobilized microparticles (VEGF-MPs). VEGF-MPs prolong VEGFR-2 and Akt phosphorylation in cord blood-derived late outgrowth endothelial progenitor cells (OEPCs). In vivo, OEPC aggregates containing VEGF-MPs show higher survival than those treated with sVEGF. Additionally, VEGF-MPs decrease miR-17 expression in OEPCs, thus increasing the expression of its target genes CDKN1A and ZNF652. The therapeutic effect of OEPCs is improved in vivo by inhibiting miR-17. Overall, our data show an experimental approach to improve therapeutic efficacy of proangiogenic cells for the treatment of ischemic diseases.Soluble vascular endothelial growth factor (VEGF) enhances vascular engraftment of transplanted cells but the efficacy is low. Here, the authors show that VEGF-immobilized microparticles prolong survival of endothelial progenitors in vitro and in vivo by downregulating miR17 and upregulating CDKN1A and ZNF652

Renewable energy production planning in the north-east of Italy by means of multi-criteria analysis

The excessive energy reliance on fossil fuels, together with the need to assure energy supplies and the will of reducing environmental emissions in order to comply with Kyoto\u2019s objectives, has fostered the interest towards energy savings and renewable energy. In Italy, many initiatives have been proposed regarding renewable fuels. These projects range from heat production fed by ligneous-cellulosic and undergrowth residues, to power plants coupled to anaerobic digesters fuelled by animal dejections, Combined Heating-Power (CHP) plants fed by vegetal oil together with district heating (DH), and Combined Cooling-Heating and Power (CCHP), all these projects being focused on energy saving. Such initiatives, in limited territorial contexts (Regions, Districts and Municipalities) are often in competition with each other, both for the economic incentives and the availability of energy sources. Public bodies\u2019 decisions on which plant has to be firstly financed, because of its major benefits in terms of both energy supply and inhabitants\u2019 wellbeing, have thus achieved major importance. Multicriteria analysis therefore appears as a natural tool in order to support such decisional process. This memoir shows a real case study in which the Analytic Hierarchy Process (AHP) has been applied to choose the priority of financing different energy plants, in order to reduce the dependency from fossil fuels and improve the overall efficiency of an area in the North-East of Italy. A survey on 16 municipalities in the district of Udine (Italy) is presented. Various feasible plants have been evaluated by means of the AHP regarding technical, economic, environmental and social issues. Technical, economic and environmental criteria were furthermore disaggregated into more detailed sub-criteria. A pairwise comparison between different options was then conducted \u2013 where feasible \u2013 through real design data, while a panel of experts evaluated the non-quantifiable criteria. However, having been the will of the public administration to finance projects which better complained with the Kyoto\u2019s objectives, the environmental aspect always resulted as the main criterion. As a consequence of this analysis, the best alternative has been identified in a CCHP plant serving the \u2018Ham District\u201d in San Daniele, well-known on international level. The AHP has been confirmed as an efficient tool to promote communication and participation of all the actors who take part in the decisional process