74 research outputs found
Analysis and Optimization of a Puffer-type Water Heater☆
Abstract In this paper we present the design optimization of a Puffer-type water heater for sanitary water production in residential buildings. The optimization study is performed with the aim to fulfill the design requirements of the heater, i.e. the provided mass flow rate and the outlet water temperature, while minimizing the surface area of the coil characterizing the Puffer and thus reducing the overall cost of the device. The coil diameter and pitch and the diameter of the pipe composing the coil are analyzed in the optimization study. Starting from available correlations providing the heat transfer rate between the sanitary water and the heated water surrounding the coil, a simplified thermal resistance model of the heat transfer process within the heater is developed. The analysis show a significant impact on the overall heat transfer rate between the sanitary water and the heated water when the geometrical parameters of the coil are varied. Using an optimal value of the pitch to pipe diameter of the coil for a given coil diameter in particular, it is possible to maximize the heat transfer rate and thus minimize the size of the coil. As a first step, the optimization study is performed by introducing sizing constraints allowing for sharing the same coil among several types of water heaters. In this case, a reduction as high as 14% of the coil surface area can be obtained, whereas a reduction as high as 23% can be achieved if the optimization is performed free of such constraints
Unveiling the morphogenetic code: A new path at the intersection of physical energies and chemical signaling
In this editorial, we discuss the remarkable role of physical energies in the control of cell signaling networks and in the specification of the architectural plan of both somatic and stem cells. In particular, we focus on the biological relevance of bioelectricity in the pattern control that orchestrates both developmental and regenerative pathways. To this end, the narrative starts from the dawn of the first studies on animal electricity, reconsidering the pioneer work of Harold Saxton Burr in the light of the current achievements. We finally discuss the most recent evidence showing that bioelectric signaling is an essential component of the informational processes that control pattern specification during embryogenesis, regeneration, or even malignant transformation. We conclude that there is now mounting evidence for the existence of a Morphogenetic Code, and that deciphering this code may lead to unprecedented opportunities for the development of novel paradigms of cure in regenerative and precision medicine
Oxytocin Modulates Osteogenic Commitment in Human Adipose-Derived Stem Cells
Human adipose-derived stem cells (hASCs) are commonly harvested in minimally invasive contexts with few ethical concerns, and exhibit self-renewal, multi-lineage differentiation, and trophic signaling that make them attractive candidates for cell therapy approaches. The identification of natural molecules that can modulate their biological properties is a challenge for many researchers. Oxytocin (OXT) is a neurohypophyseal hormone that plays a pivotal role in the regulation of mammalian behavior, and is involved in health and well-being processes. Here, we investigated the role of OXT on hASC proliferation, migratory ability, senescence, and autophagy after a treatment of 72 h; OXT did not affect hASC proliferation and migratory ability. Moreover, we observed an increase in SA-β-galactosidase activity, probably related to the promotion of the autophagic process. In addition, the effects of OXT were evaluated on the hASC differentiation ability; OXT promoted osteogenic differentiation in a dose-dependent manner, as demonstrated by Alizarin red staining and gene/protein expression analysis, while it did not affect or reduce adipogenic differentiation. We also observed an increase in the expression of autophagy marker genes at the beginning of the osteogenic process in OXT-treated hASCs, leading us to hypothesize that OXT could promote osteogenesis in hASCs by modulating the autophagic process
Appropriateness of Mini-Invasive Approaches for Nausea and Vomiting Refractory to Medical Therapy in Palliative Care Setting: A Case Report
Introduction: Nausea and vomiting are frequent multifactorial symptoms in oncological patients. These manifestations, mainly affecting the advanced disease stages, may lead to existential, psychological, and physical suffering, with a negative impact on the quality of life (QoL) of the individual and his family. The medical approach makes use of a wide range of drugs, with different antiemetic potency and various mechanisms of action, taking into account the etiology and the patient’s response to the different therapeutic strategies. In recent years, in addition to pharmacological treatments, some endoscopic procedures have been integrated into clinical practice as promising palliative approaches. Case Presentation: Herein, we describe and discuss a case of a 64-year-old female affected by advanced stage pancreatic adenocarcinoma, in which different techniques – both medical and endoscopic – have been used to approach a refractory symptomatology with a negative impact on the patient’s QoL. In the context of a multidisciplinary approach in primary palliative care, a tailored intervention encompassing invasive methods for palliative purposes, may be considered adequate and appropriate when the prognostic expectation and the physical functionality indices allow it. Conclusion: Minimally invasive palliative interventions should be offered to patients with advanced cancer when symptoms become refractory to standard medical therapies, as part of the holistic approach in modern treatments. Therefore, the integration of an early palliative approach into the patient’s therapeutic path becomes essential for the management of all the individual’s needs
Cytochalasin B Modulates Nanomechanical Patterning and Fate in Human Adipose-Derived Stem Cells
Cytoskeletal proteins provide architectural and signaling cues within cells. They are able to reorganize themselves in response to mechanical forces, converting the stimuli received into specific cellular responses. Thus, the cytoskeleton influences cell shape, proliferation, and even differentiation. In particular, the cytoskeleton affects the fate of mesenchymal stem cells (MSCs), which are highly attractive candidates for cell therapy approaches due to their capacity for self-renewal and multi-lineage differentiation. Cytochalasin B (CB), a cyto-permeable mycotoxin, is able to inhibit the formation of actin microfilaments, resulting in direct effects on cell biological properties. Here, we investigated for the first time the effects of different concentrations of CB (0.1–10 μM) on human adipose-derived stem cells (hASCs) both after 24 h (h) of CB treatment and 24 h after CB wash-out. CB influenced the metabolism, proliferation, and morphology of hASCs in a dose-dependent manner, in association with progressive disorganization of actin microfilaments. Furthermore, the removal of CB highlighted the ability of cells to restore their cytoskeletal organization. Finally, atomic force microscopy (AFM) revealed that cytoskeletal changes induced by CB modulated the viscoelastic properties of hASCs, influencing their stiffness and viscosity, thereby affecting adipogenic fat
Late cardiac events after childhood cancer: Methodological aspects of the pan-european study pancaresurfup
Background and Aim Childhood cancer survivors are at high risk of long-Termadverse effects of cancer and its treatment, including cardiac events. The pan-European PanCareSurFup study determined the incidence and risk factors for cardiac events among childhood cancer survivors. The aim of this article is to describe the methodology of the cardiac cohort and nested case-control study within PanCareSurFup. Methods Eight data providers in Europe participating in PanCareSurFup identified and validated symptomatic cardiac events in their cohorts of childhood cancer survivors. Data onsymptomatic heart failure, ischemia, pericarditis, valvular disease and arrhythmia were collected and graded according to the Criteria for Adverse Events. Detailed treatment data, data on potential confounders, lifestyle related risk factors and general health problems were collected. Results The PanCareSurFup cardiac cohort consisted of 59,915 5-year childhood cancer survivors with malignancies diagnosed between 1940 and 2009 and classified according to the International Classification of Childhood Cancer 3. Different strategies were used to identify cardiac events such as record linkage to population/ hospital or regional based databases, and patient-And general practitioner-based questionnaires. Conclusion The cardiac study of the European collaborative research project PanCareSurFup will provide the largest cohort of 5-year childhood cancer survivors with systematically ascertained and validated data on symptomatic cardiac events. The result of this study can provide information to minimize the burden of cardiac events in childhood cancer survivors by tailoring the follow-up of childhood cancer survivors at high risk of cardiac adverse events, transferring this knowledge into evidence-based clinical practice guidelines and providing a platformfor future research studies in childhood cancer patients. © 2016 Feijen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Root angle is controlled by EGT1in cereal crops employing anantigravitropic mechanism
Root angle in crops represents a key trait for efficient capture of soil resources. Root angle is determined by competing gravitropic versus anti-gravitropic offset (AGO) mechanisms. Here we report a new root angle regulatory gene termed ENHANCED GRAVITROPISM1 (EGT1) that encodes a putative AGO component, whose loss of function enhances root gravitropism. Mutations in barley and wheat EGT1 genes confer a striking root phenotype, where every root class adopts a steeper growth angle. EGT1 encodes a F-box and Tubby domain containing protein which is highly conserved across plant species. Haplotype analysis found that natural allelic variation at the barley EGT1 locus impacts root angle. Gravitropic assays indicated that Hvegt1 roots bend more rapidly than wildtype. Transcript profiling revealed Hvegt1 roots deregulate ROS homeostasis and cell wall-loosening enzymes and cofactors. ROS imaging shown that Hvegt1 root basal meristem and elongation zone tissues have reduced levels. Atomic Force Microscopy measurements detected elongating Hvegt1 root cortical cell walls are significantly less stiff than wildtype. In situ analysis identified HvEGT1 is expressed in elongating cortical and stele tissues, which are distinct from known root gravitropic perception and response tissues in the columella and epidermis, respectively. We propose that EGT1 controls root angle by regulating cell wall stiffness in elongating root cortical tissue, counteracting the gravitropic machinery’s known ability to bend the root via its outermost tissues. We conclude that root angle is controlled by EGT1 in cereal crops employing a novel anti-gravitropic mechanism
Diagnosis and treatment of urticaria and angioedema: a worldwide perspective
Urticaria and angioedema are common clinical conditions representing a major concern for physicians and patients alike. The World Allergy Organization (WAO), recognizing the importance of these diseases, has contributed to previous guidelines for the diagnosis and management of urticaria. The Scientific and Clinical Issues Council of WAO proposed the development of this global Position Paper to further enhance the clinical management of these disorders through the participation of renowned experts from all WAO regions of the world. Sections on definition and classification, prevalence, etiology and pathogenesis, diagnosis, treatment, and prognosis are based on the best scientific evidence presently available. Additional sections devoted to urticaria and angioedema in children and pregnant women, quality of life and patient-reported outcomes, and physical urticarias have been incorporated into this document. It is expected that this article will supplement recent international guidelines with the contribution of an expert panel designated by the WAO, increasing awareness of the importance of urticaria and angioedema in medical practice and will become a useful source of information for optimum patient management worldwide
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