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21.

Irrigated agriculture plays a vital role for the socio-economic development of the Mediterranean area, although it has significant impacts on both water and energy resources. Therefore, in a context in which water resources are also experiencing increasing pressures, there is an urgent need for supporting their sustainable management. This may be an extremely challenging task, especially at the local scale, due to the several interconnected dynamics affecting the state of a complex irrigation system. In fact, multiple actors are involved in decision-making processes, and the use of natural resources (and their mutual interactions) strongly depends on their behaviors, which affect the system as a whole. In this context, the present study proposes an integrated methodology, based on the Water Energy Food Nexus (WEFN), specifically focused on the sustainable management of water resources for irrigation. Firstly, a model based on Causal Loop Diagrams (CLD) is developed in order to get a deep insight into the key dynamics behind a complex irrigation system. Secondly, three indices based on the “footprint” concept are identified, in order to synthesize such dynamics. The integration of these two approaches support investigating the whole system and, particularly, understanding the influence of multiple decisional actors on it, as well as the role of a set of key drivers and constraints. This might also allow drawing some relevant conclusions, useful for supporting effective decisions oriented to a sustainable water resources management. Specific reference is made to a case study, the Capitanata irrigation system, located in the Southern Italy.

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Endometrial cancer (EC) is a deleterious condition which strongly affects a woman’s quality of life. Although aggressive interventions should be considered to treat high-grade EC, a conservative approach should be taken into consideration for women wishing to conceive. In this scenario, we present an overview about the EC fertility-sparing approach state of art. Type I EC at low stage is the only histological type which can be addressed with a fertility-sparing approach. Moreover, no myometrium and/or adnexal invasion should be seen, and lymph-vascular space should not be involved. Regarding the pharmaceutical target, progestins, in particular medroxyprogesterone acetate (MPA) or megestrol acetate (MA), are the most employed agent in conservative treatment of early-stage EC. The metformin usage and hysteroscopic assessment is still under debate, despite promising results. Particularly strict and imperious attention should be given to the follow-up and psychological wellbeing of women, especially because of the double detrimental impairment: both EC and EC-related infertility consequences.  相似文献   
25.
A detailed stratigraphic investigation of the intercalation mechanism when graphite electrodes are immersed inside diluted perchloric(HClO4)and sulfuric(H2SO4)electrolytes is obtained by comparing results when graphite crystals are simply immersed in the same acid solutions.By combining time-of-flight secondary ion mass spectrometry(ToF-SIMS)and in-situ atomic force microscopy(AFM),we provide a picture of the chemical species involved in the intercalation reaction.The depth intensity profile of the ion signals along the electrode crystal clearly shows a more complex mechanism for the intercalation process,where the local morphology of the basal plane plays a crucial role.Solvated anions are mostly located within the first tens of nanometers of graphite,but electrolytes also diffuse inside the buried layers for hundreds of nanometers,the latter process is also aided by the presence of mesoscopic crystal defects.Residual material from the electrolyte solution was found localized in well-defined circular spots,which represent preferential interaction areas.Interestingly,blister-like micro-structures similar to those observed on the highly oriented pyrolytic graphite(HOPG)surface were found in the buried layers,confirming the equivalence of the chemical condition on the graphite surface and in the underneath layers.  相似文献   
26.
Peripheral artery occlusive disease is an emerging cardiovascular disease characterized by the blockage of blood vessels in the limbs and is associated with dysfunction, gangrene, amputation, and a high mortality risk. Possible treatments involve by-pass surgery using autologous vessel grafts, because of the lack of suitable synthetic small-diameter vascular prosthesis. One to five percent of patients experience vascular graft infection, with a high risk of haemorrhage, spreading of the infection, amputation and even death. In this work, an infection-proof vascular graft prototype was designed and manufactured by electrospinning 12.5% w/v poly-L-lactic-co-glycolic acid solution in 75% v/v dichloromethane, 23.8% v/v dimethylformamide and 1.2% v/v water, loaded with 0.2% w/wPLGA. Polymer and tobramycin concentrations were selected after viscosity and surface tension and after HPLC-UV encapsulation efficiency (EE%) evaluation, respectively. The final drug-loaded prototype had an EE% of 95.58% ± 3.14%, with smooth fibres in the nanometer range and good porosity; graft wall thickness was 291 ± 20.82 μm and its internal diameter was 2.61 ± 0.05 mm. The graft’s antimicrobic activity evaluation through time-kill assays demonstrated a significant and strong antibacterial activity over 5 days against Staphylococcus aureus and Escherichia coli. An indirect cell viability assay on Normal Human Dermal Fibroblasts (NHDF) confirmed the cytocompatibility of the grafts.  相似文献   
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The capillary extrusion flow properties of novel engineering thermoplastic phenolphthalein poly(ether-ether-sulphone) (PES-C) have been investigated using capillary rheometer. The dependence of viscosity on the wall shear rate and temperatures were obtained. The flow activation energy was found to decrease with shear rate but to be constant with shear stress. The entrance effect was calculated and from which the extensional behavior was estimated using Cogswell's method. From the extrudate swell ratio the principal normal stress was evaluated and a temperature-independent correlation was observed when they were plotted against shear stress. The melt fracture phenomena were checked and discussed also. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:951–958, 1997  相似文献   
28.
The C-terminal aminoacidic sequence from NPM1-mutated protein, absent in normal human tissues, may serve as a leukemia-specific antigen and can be considered an ideal target for NPM1-mutated acute myeloid leukemia (AML) immunotherapy. Different in silico instruments and in vitro/ex vivo immunological platforms have identified the most immunogenic epitopes from NPM1-mutated protein. Spontaneous development of endogenous NPM1-mutated-specific cytotoxic T cells has been observed in patients, potentially contributing to remission maintenance and prolonged survival. Genetically engineered T cells, namely CAR-T or TCR-transduced T cells, directed against NPM1-mutated peptides bound to HLA could prospectively represent a promising therapeutic approach. Although either adoptive or vaccine-based immunotherapies are unlikely to be highly effective in patients with full-blown leukemia, these strategies, potentially in combination with immune-checkpoint inhibitors, could be promising in maintaining remission or preemptively eradicating persistent measurable residual disease, mainly in patients ineligible for allogeneic hematopoietic stem cell transplant (HSCT). Alternatively, neoantigen-specific donor lymphocyte infusion derived from healthy donors and targeting NPM1-mutated protein to selectively elicit graft-versus-leukemia effect may represent an attractive option in subjects experiencing post-HSCT relapse. Future studies are warranted to further investigate dynamics of NPM1-mutated-specific immunity and explore whether novel individualized immunotherapies may have potential clinical utility in NPM1-mutated AML patients.  相似文献   
29.
ABSTRACT

In this work we investigated the effects of oil phase lipophilicity on in vitro drug release from topical o/w microemulsions (MEs) containing low percentages of emulsifiers. Three different lipids, isopropyl myristate (IPM), isopropyl palmitate (IPP), and isopropyl stearate (IPS), whose lipophilicity increased in the order IPM < IPP <IPS, were used as oil phase to prepare o/w MEs containing low amounts (7.7% w/w) of two surfactant/cosurfactant mixtures, isoceteth-20/glyceryl oleate (5:2) (MEs 1–3) and oleth-20/glyceryl oleate (5:2) (MEs 4–6). All the MEs were prepared using the phase inversion temperature (PIT) method.

Three active compounds (0.5% w/w), Naproxen (NAP), Idebenone (IDE), and Butylmethoxydibenzoylmethane (BMBM), were selected as model drugs and their release rates from PIT MEs were evaluated using Franz-type diffusion cells. All the MEs gave a mean droplet diameter ranging from 28 to 44 nm and showed a single peak in size distribution. The addition of IDE to MEs 1–6 did not significantly change ME droplet size. On the contrary, an increase of the droplet size beyond the ME limit (150 nm) was observed when isoceteth-20 was used as surfactant to prepare MEs containing NAP or MEs containing BMBM and IPS as oil phase. Pseudo-first order release rates were observed only for NAP from MEs 1–3, while MEs containing IDE showed an initial slow release followed by an increased release of the test compound. The release rate constants were found to be dependent on the ME composition and on the active compound incorporated. The highest release rate was observed from ME 1 containing IPM as oil phase and NAP as drug. As regards BMBM, its release rate was not calculated since no release was observed until 6 h from the beginning of the experiment. The cumulative amount of active compound released after 22 h was inversely related to drug lipophilicity (NAP Log P = 2,9; IDE Log P 3,5; BMBM Log P 4,8). These findings could be attributable to a reduced thermodynamic activity of the drugs in the vehicles containing the most lipophilic oil phase due to an increase of drug solubility which could lead to an unfavorable drug partition from the oil phase. The results of this study suggest that the choice of proper combinations of oil phase lipids and emulsifiers may allow achieving drug controlled delivery from topical o/w MEs with low emulsifier content.  相似文献   
30.
Herein we propose the D ‐Trp‐Phe sequence within an inverse type II β‐turn as a new kind of pharmacophoric motif for μ‐opioid receptor (MOR) cyclopeptide agonists. Initially, we observed that c[Tyr‐D ‐Pro‐D ‐Trp‐Phe‐Gly] ( 4 ), an analogue of endomorphin‐1 (H‐Tyr‐Pro‐Trp‐Phe‐NH2) lacking the crucial protonatable amino group of Tyr 1, is a MOR agonist with 10?8 M affinity. Molecular docking analysis suggested that the relevant interactions with the receptor involve D ‐Trp‐Phe. The bioactive conformation of this region was investigated by selected derivatives of 4 designed to adopt an inverse type II β‐turn. These efforts led to c[Tyr‐Gly‐D ‐Trp‐Phe‐Gly] ( 14 ) and to the cyclotetrapeptide c[D ‐Asp‐1‐amide‐β‐Ala‐D ‐Trp‐Phe] ( 15 ), showing improved nanomolar affinity. Both 14 and 15 selectively bind MOR, as they have negligible affinity for the κ‐ and δ‐opioid receptors. Both 14 and 15 behave as partial MOR agonists in functional assays. Conformational and docking analyses confirm the role of the inverse β‐turn in binding. These results indicate that the D ‐Trp‐Phe inverse β‐turn structure can be used for designing non‐endomorphin‐like peptidomimetic opioid agonists in general, characterized by an atypical mechanism of interaction between ligand and receptor.  相似文献   
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