Fouling mechanism elucidation in membrane bioreactors by bespoke physical cleaning

Cake layer deposition on a membrane surface can determine both external and internal membrane fouling through negatively affecting the total filtration resistance while exerting a positive effect as a pre-filter. Membranes are usually subjected to a periodic cake layer removal through routine physical cleaning, specifically permeate backwashing of hollow fiber membranes, or enhanced cleaning through, for example, chemically-enhanced backwashing. Physical cake layer removal is crucial for sustaining permeability, yet the effect of different physical cleaning modes remains poorly evaluated. The present work attempts to analyze physical cake layer removal through the application of specific cleaning methods and the impact of these on the subsequent resistance. The constituent contributions to the overall resistance are appraised by means of the Resistances In-Series model, with the aim of producing a robust protocol for quantifying these discrete contributors. The results, based in part on published data, show the proposed approach to reliably determine the relative contribution of the different resistance components to within 0.1 · 1012 m−1 across a range of different bench and pilot-scale plants, confirming the resilience of the method

The PERK(s) of having your own niche: how Acute Myeloid Leukaemia transforms the Bone Marrow Microenvironment

Mesenchymal stromal cells (MSC), that generate multiple bone marrow (BM) cell types, such as adipocytes and osteoblasts, contribute to the BM microenvironment cellular diversity, critical to supporting functional haematopoiesis. Mouse model research has shown that acute myeloid leukaemia (AML) alters the BM niche, inducing MSC quiescence, impeding adipogenic differentiation, and compromising haematopoiesis. In this context, it is still unclear whether AML cells directly inhibit haematopoiesis or if this is mediated via alterations of the BM niche. We hypothesized that AML propagation induces stresses, such as oxidative stress, starvation or hypoxia, that lead to endoplasmic reticulum (ER) stress in the BM niche, ultimately leading to the BM failure observed in patients. Here, with combined ex vivo and in vivo studies, we show that AML induces in MSCs an ER stress response known as unfolded protein response (UPR). UPR signals through three branches, PERK, IRE1 and ATF6 to regulate protein synthesis rates, lipid metabolism and apoptosis. Our data reveal the activation of UPR in MSC undergoing adipogenic differentiation. Using a lentiviral conditional overexpression approach, we show that PERK activation reduces MSC proliferative capacities, triggers a cytostatic effect, and shows no apoptosis. Remarkably, MSC adipogenic differentiation is impaired upon conditional PERK activation, while not upon IRE1 overexpression. These data are in line with the adipogenic differentiation blockage observed in AML patients' BM. Furthermore, by using an ectopic humanised BM niche in mice, we show that PERK activation in MSC results in hematopoietic lineage skewing with increased myeloid cells. These findings demonstrate the role of UPR activation as a mechanism responsible for BM alteration. Our study provides new therapeutic opportunities to restore BM functions by targeting UP

Influence of the Height of Municipal Solid Waste Landfill on the Formation of Perched Leachate Zones

Waste settlement as well as consolidation phenomena, which occur inside a landfill for municipal solid waste (MSW), can cause a decrease in waste permeability. This can lead to a reduction in conveyance of the leachate drainage system. It is therefore possible that a so-called perched leachate zone will form. Such a zone is constituted by an area in the body of the landfill where the leachate is temporarily trapped and is unable to infiltrate downward. This phenomenon is influenced by many factors, which include rain infiltration rate, waste moisture and composition, landfill height, and so on. The main aim of the paper is to elucidate the role played by landfill height in the formation of perched leachate zones using a one-dimensional (1D) mathematical model. The model allows for the simulation of the perco- lation fluxes throughout an MSW landfill based on mass-balance equations. The results showed a different response in terms of flow rates throughout the landfill, highlighting the important role of landfill height in the formation of perched leachate zones. Landfill height influences not only the formation of perched leachate zones but also their extension throughout the body of the landfill

static and dynamic response of titanium alloy produced by electron beam melting

Abstract The suitability of Titanium alloys for many specialized applications requiring excellent performances at both static and dynamic strain rates, benefits of modern manufacturing technologies like the additive manufacturing, oriented toward the obtainment of complicated component shapes. The EBM methodology for the production of Ti6Al4V components is based on the localized melting of alloy powders by way of guided electron beams scanning the powder volume by successive planar trajectories; for this reason, the whole production process may confer a certain degree of anisotropy to the components. The material behavior of the EBM alloy may be orientation-dependent in terms of stress-strain elastoplastic response as well as in terms of damage sensitivity and ductile fracture under given triaxiality histories. The static and dynamic behavior of a sintered Ti6Al4V alloy is investigated here by way of quasistatic tension-torsion tests and dynamic tensile Hopkinson bar (SHTB) tests. The outcome of the latter experiments, compared to similar tests results from the literature concerning Ti alloy obtained by classical metallurgical techniques, gives some indications about how the technological process may affect the final performance of the material and the component

Exosomes from metastatic cancer cells transfer amoeboid phenotype to non-metastatic cells and increase endothelial permeability: their emerging role in tumor heterogeneity

The goal of this study was to understand if exosomes derived from high-metastatic cells may influence the behavior of less aggressive cancer cells and the properties of the endothelium. We found that metastatic colon cancer cells are able to transfer their amoeboid phenotype to isogenic primary cancer cells through exosomes, and that this morphological transition is associated with the acquisition of a more aggressive behavior. Moreover, exosomes from the metastatic line (SW620Exos) exhibited higher ability to cause endothelial hyperpermeability than exosomes from the non metastatic line (SW480Exos). SWATH-based quantitative proteomic analysis highlighted that SW620Exos are significantly enriched in cytoskeletal-associated proteins including proteins activating the RhoA/ROCK pathway, known to induce amoeboid properties and destabilization of endothelial junctions. In particular, thrombin was identified as a key mediator of the effects induced by SW620Exos in target cells, in which we also found a significant increase of RhoA activity. Overall, our results demonstrate that in a heterogeneous context exosomes released by aggressive sub-clones can contribute to accelerate tumor progression by spreading malignant properties that affect both the tumor cell plasticity and the endothelial cell behavior

Zespół padaczkowy z drgawkami połowiczymi i porażeniem połowiczym. Wyniki badania za pomocą rezonansu magnetycznego u trzyletniego chłopca

The term ‘hemiconvulsion-hemiplegia-epilepsy syndrome’ (HHE) was first used by Gastaut et al. to describe the sequential combination of unilateral or predominandy unilateral clonic seizures (hemiconvulsion), occurring during the first 2 years of life, immediately followed by an ipsilateral flaccid hemiplegia lasting 7 or more days. In the following phase partial epileptic seizures occur. We report a case of HHE syndrome in a 3-year-old boy with partial seizures (hemiconvulsion lasting 15–30 minutes) followed by left hemiplegia and hyporeflexia. Magnetic resonance imaging showed diffuse and high signal hyperintensity of the whole right cerebral hemisphere. Diffusion-weighted images showed a reduction of the apparent diffusion coefficient in the subcortical region. Magnetic resonance arteriography showed a narrow flow signal in the distal territory of the right middle cerebral artery. The authors emphasize the importance of neuroradiological findings in early diagnosis and in the follow-up of HHE syndrome.Określenia zespół padaczkowy z drgawkami połowiczymi i z porażeniem połowiczym” (hemiconvulsion-hemiplegia epilepsy – HHE) użyli po raz pierwszy Gastaut i wsp., aby opisać połączenie jednostronnych lub głównie jednostronnych drgawek klonicznych, pojawiających się w pierwszych dwóch latach życia, po których następuje tożstronne wiotkie porażenie połowicze utrzymujące się przez co najmniej tydzień. Następnie występują napady padaczkowe częściowe. W artykule przedstawiono przypadek zespołu HHE u trzyletniego chłopca z napadami częściowymi (drgawki połowicze trwające 15–30 minut), po których nastąpiło lewostronne porażenie połowicze z osłabionymi odruchami głębokimi. W badaniu za pomocą rezonansu magnetycznego uwidoczniono rozlane zmiany hiperintensywne w całej prawej półkuli mózgu. W obrazowaniu dyfuzji stwierdzono zmniejszenie współczynnika dyfuzji w obszarach podkorowych. W arteriografii rezonansu magnetycznego uwidoczniono wąski sygnał przepływu w dystalnych gałęziach prawej tętnicy środkowej mózgu. Autorzy podkreślają znaczenie wyników badań obrazowych układu nerwowego we wczesnym rozpoznaniu i obserwacji chorych na HHE

Pesticide and plasticizer residues in citrus essential oils from different countries.

Residue analyses are very important in the quality control of citrus essential oils. Organophosphorus and organochlorine pesticides, phosphorated plasticizers and chloroparaffins contamination were investigated by HRGC with FPD and ECD detectors in 120 citrus essential oils produced in Italy and in 70 from other countries in the crop year 2006-2007. Results showed that the largest pesticide quantities were found in oils from Brazil and Spain. The presence of such residues might be the result of an improper use of pesticide in citrus growing or of previous contamination of the extractors. However, the pesticide levels showed a measurable decrease in relation to past production years. The absence of phosporated plasticizers and chloroparaffins can be the result of either improvement of the procedures used during the production cycle or in the storage of the essential oils compared with previous years

An exploratory study of MoS2 as anode material for potassium batteries

Potassium-based batteries represent one of the emerging classes of post-lithium electrochemical energy storage systems in the international scene, due to both the abundance of raw materials and achievable cell potentials not far from those of lithium batteries. In this context, it is important to define electrodes and electrolytes that give reproducible performance and that can be used by different research groups as an internal standard when developing new materials. We propose molybdenum disulfide (MoS2) as a valid anode choice, being a commercial and easily processable material, the 2D layered structure of which is promising for large potassium ions reversible storage. It has been proven to work for hundreds of cycles, keeping a constant specific capacity around 100 mAh g−1 while also preserving its electrochemical interphase and morphology

Planting Date and Different N-Fertilization Rates Differently Modulate Agronomic and Economic Traits of a Sicilian Onion Landrace and of a Commercial Variety

The onion is one of the most widespread bulb vegetables worldwide. Onion cultivation is common in Sicily, as is the use of local genotypes. Cultivation practices are of particular interest in optimizing yield, quality, and profits. The aim of this study was to assess the agronomic response of a Sicilian landrace (Bianca Calda di Comiso, coded L1) and a commercial variety (Bianca di Maggio, coded V1) to different planting dates and N fertilization rates. An economic appraisal was also performed. The two genotypes were assessed using an experimental split-split-plot design with four levels of nitrogen rates (0, 80, 160, and 220 kg N ha−1) and two different planting dates (8 October 2005 to 9 October 2006 for the early planting date, and 27 December 2005 to 30 December 2006 for the traditional planting date). The marketable yield and production parameters were significantly influenced by the nitrogen dose: higher doses led to a higher total yield, with yield peaks above 60 t ha−1 and the marketable yield ranging from 23% to 54%. Simultaneously, decreases in the firmness (from 7% to 19%) and scale content (from 1% to 3%) were also reported. The L1 landrace showed a higher production than the V1 variety. The crop year did not significantly affect the results, and the traditional planting date appeared to be the most suitable choice in obtaining the best agronomic response. Economic analysis showed that the L1 landrace, with high-N application treatments, produced greater net benefits and marginal rates of return. Thus, the L1 landrace exposed to the highest dosages of nitrogen (160 or 220 kg ha−1) and transplanted during the traditional planting period is the best choice from agronomic and economic points of view

SERUM IONIZED MAGNESIUM IN DIABETIC OLDER PERSONS

Objective. Several alterations of magnesium metabolism have been associated with type 2 diabetes pathophysiology, a condition particularly frequent in older persons. We aimed to evaluate serum total (Mg-tot) and serum ionized magnesium (Mg-ion) in older persons with type 2 diabetes in order to explore clinically applicable methods for the detection of magnesium deficit. Material/Methods: Mg-tot and Mg-ion were measured in 105 fasting subjects with type 2 diabetes (mean age: 71.10.8 years; M/F: 45/60) and in 100 age-matched non-diabetic control persons (mean age: 72.20.8 years; M/F: 42/58). Results: Mg-ion concentrations were significantly lower in diabetic persons compared with controls (0.490.05 mmol/L vs. 0.550.05 mmol/L; p<0.001). Mg-tot was also slightly but significantly lower in diabetic patients (0.820.007 mmol/L vs. 0.840.006 mmol/L; p<0.05). There was an almost complete overlap in the values of Mg-tot in older diabetic patients and controls; conversely, 44.8% of diabetic patients had Mg-ion values below 0.47 mmol/L, while none of the controls did. After adjustment for age, sex, BMI, and triglycerides, Mg-tot was significantly associated with FBG in all the participants (p<0.05) and Mg-ion was significantly associated with FBG in all the participants (p<0.01) and with HbA1c in diabetic participants (p<0.001). Conclusions: Alterations of magnesium serum concentrations are common in type 2 diabetic older adults; Mg-ion evaluation may help to identify subclinical magnesium depletion (i.e. in patients with normal Mg-tot); the close independent associations of Mg-tot and Mg-ion with FBG and with HbA1c reinforce the possible link between magnesium homeostasis and altered glucose metabolism