Stoichiometry dependence of the evolution of the irradiated-induced defect clusters in lanthanum-doped ceria

To study the stoichiometry dependence of irradiation e ects in fluorite-type mixed oxide nuclear fuel (UPuO2), ion implantation in La doped ceria was used. Cerium dioxide single crystals with 0 mol%, 5 mol% and 25 mol% La concentration were irradiated with 1 MeV Kr ions at 800 C. In-situ transmission electron microscope (TEM) was utilized to observe the the damage process and defects created by the ion beam irradiation. Dislocation loops were observed after irradiation and were determined to be on {111} planes, but not on {220} or {200} planes. Ab substantial difference in the average size of dislocation loops for 0 %, 5% and 25% cases was observed at several doses.The growth rate of dislocation loops and the oxygen vacancy di usivity were found to be inversely correlated.

Effect of high densities on growth, stress response and plasma amino acid levels in senegalese sole (Solea senegalensis, Kaup 1858)

Dissertação de mest. em Aquacultura e Pescas, Faculdade de Ciências do Mar e do Ambiente, Univ. do Algarve, 2006

Elemental Anisotropic Growth and Atomic-Scale Structure of Shape-Controlled Octahedral Pt–Ni–Co Alloy Nanocatalysts

Multimetallic shape-controlled nanoparticles offer great opportunities to tune the activity, selectivity, and stability of electrocatalytic surface reactions. However, in many cases, our synthetic control over particle size, composition, and shape is limited requiring trial and error. Deeper atomic-scale insight in the particle formation process would enable more rational syntheses. Here we exemplify this using a family of trimetallic PtNiCo nanooctahedra obtained via a low-temperature, surfactant-free solvothermal synthesis. We analyze the competition between Ni and Co precursors under coreduction “one-step” conditions when the Ni reduction rates prevailed. To tune the Co reduction rate and final content, we develop a “two-step” route and track the evolution of the composition and morphology of the particles at the atomic scale. To achieve this, scanning transmission electron microscopy and energy dispersive X-ray elemental mapping techniques are used. We provide evidence of a heterogeneous element distribution caused by element-specific anisotropic growth and create octahedral nanoparticles with tailored atomic composition like Pt1.5M, PtM, and PtM1.5 (M = Ni + Co). These trimetallic electrocatalysts have been tested toward the oxygen reduction reaction (ORR), showing a greatly enhanced mass activity related to commercial Pt/C and less activity loss than binary PtNi and PtCo after 4000 potential cycles.

Clinical Studies on conformal radiotherapy combined with epidermal growth factor receptor-tyrosine kinase inhibitor in second-line treatment of non-small cell lung cancer

Purpose: To study the effect of conformal radiotherapy combined with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in the second-line treatment of non-small cell lung cancer (NSCLC). Methods: A total of 316 patients attending Shanghai Pulmonary Hospital affiliated to Tongji University, were divided into two groups: 106 patients were treated with conformal radiotherapy combined with EGFR-TKI (gefitinib, 250 mg/day; or erlotinib, 150 mg/day), while 210 patients were treated with EGFRTKI alone. Some factors, including adverse reactions (AR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and one-year and two-year survival rate, were evaluated. Results: No obvious difference was observed in AR between the two groups (p > 0.05). In the combination therapy group, complete response (CR) was 5 cases, partial response (PR) 43 cases, and stable disease (SD) 47 cases, progressive disease (PD) was 11 cases, response rate (RR) was 45.3 %, and DCR 89.6 %. Median PFS in the combination therapy group and targeted therapy group was 6.5 and 5.0 months, respectively. On the other hand, median OS in the combination therapy group and targeted group was 14.1 and 12.6 months, respectively. One-year survival rate of the combination therapy group and EGFR-TKI group was 60.3 and 50.0 %, respectively, while the two-year survival rate was 26.3 and 19.0 %, respectively. Conclusion: Conformal radiotherapy combined with EGFR-TKI can be used as an effective second-line treatment for NSCLC.

Free- and peptide-based dietary arginine supplementation for the South American fish pacu (Piaractus mesopotamicus)

Arginine was hypothesized to be a model compound in the present study on molecular forms of indispensable amino acid (IAA) dietary supplementation. Juvenile South American pacu (Piaractus mesopotamicus) were fed diets containing arginine in a protein base (casein-wheat gluten or casein-gelatin), or the casein-wheat gluten base supplemented with dipeptide or free arginine at two levels (5 and 10 g kg(-1)). Growth and protein efficiency ratios were significantly affected by diets, but not by arginine molecular form. Three free dispensable amino acids (DAA) and four IAA in plasma were affected by diet, but plasma arginine concentrations did not differ. Plasma urea concentrations, being very low in the pacu, and hepatic arginase activities, were not affected by diet (P = 0.10-0.11), but together with plasma ornithine, mirrored the growth data. Molecular form of arginine supplementation, free or dipeptide, significantly changed several free IAA (Phe, Leu, Ile, His) and urea, with a higher mean plasma concentration in dipeptide fed fish. The dietary treatments, or molecular form of the arginine supplementation, did not change proximate composition, except that calcium levels decreased with higher dietary arginine supplementation level. The present study indicates that dipeptides can provide IAA to pacu, and that arginine supplemented in this form is utilized as efficiently as in free form.

Understanding Co-translational Protein Targeting and Lithium Dendrite Formation through Free Energy Simulations and Coarse-Grained Models

We describe the application of alchemical free energy methods and coarse-grained models to study two key problems: (i) co-translational protein targeting and insertion to direct membrane proteins to the endoplasmic reticulum for proper localization and folding, (ii) lithium dendrite formation during recharging of lithium metal batteries. We show that conformational changes in the signal recognition particle, a central component of the protein targeting machinery, confer additional specificity during the the recognition of signal sequences. We then develop a three-dimensional coarse-grained model to study the long-timescale dynamics of membrane protein integration at the translocon and a framework for the calculation of binding free energies between the ribosome and translocon. Finally, we develop a coarse-grained model to capture the dynamics of lithium deposition and dissolution at the electrode interface with time-dependent voltages to show that pulse plating and reverse pulse plating methods can mitigate dendrite growth.

Defining fluid restriction in the management of infants following cardiac surgery and understanding the subsequent impact on nutrient delivery and growth outcomes

Adequacy of nutritional intake during the postoperative period, as measured by a change in weight-for-age z-scores from surgery to the time of discharge, was evaluated in infants (n = 58) diagnosed with a congenital heart defect and admitted for surgical intervention at Miami Children’s Hospital using a prospective observational study design. Parental consent was obtained for all infants who participated in the study. ^ Forty patients had a weight available at hospital discharge. The mean preoperative weight-for-age z-score was -1.3 ±1.43 and the mean weight-for-age z-score at hospital discharge was -1.89 ±1.35 with a mean difference of 0.58 ±0.5 (P = 0.2).^ Nutritional intake during the postoperative period was inadequate based on a decrease in weight-for-age z-scores from the time of surgery until discharged home. Our findings suggested that limited fluid volume for nutrition likely contributes to suboptimal nutritional delivery during the postoperative period; however, inadequate nutrition prescription may also be an important contributing factor. Development of a nutrition protocol for initiation and advancement of nutrition support may reduce the delay in achieving patient’s nutritional goals and may attenuate the observed decrease in z-scores during the postoperative period.^

HydroxyprolineO-arabinosyltransferase mutants oppositely alter tip growth inArabidopsis thalianaandPhyscomitrella patens

Hydroxyproline O-arabinosyltransferases (HPATs) are members of a small, deeply conserved family of plant-specific glycosyltransferases that add arabinose sugars to diverse proteins including cell wall-associated extensins and small signaling peptides. Recent genetic studies in flowering plants suggest that different HPAT homologs have been co-opted to function in diverse species-specific developmental contexts. However, nothing is known about the roles of HPATs in basal plants. We show that complete loss of HPAT function in Arabidopsis thaliana and the moss Physcomitrella patens results in a shared defect in gametophytic tip cell growth. Arabidopsis hpat1/2/3 triple knockout mutants suffer from a strong male sterility defect as a consequence of pollen tubes that fail to fully elongate following pollination. Knocking out the two HPAT genes of Physcomitrella results in larger multicellular filamentous networks due to increased elongation of protonemal tip cells. Physcomitrella hpat mutants lack cell-wall associated hydroxyproline arabinosides and can be rescued with exogenous cellulose, while global expression profiling shows that cell wall-associated genes are severely misexpressed, implicating a defect in cell wall formation during tip growth. Our findings point to a major role for HPATs in influencing cell elongation during tip growth in plants.

Effects of the inclusion of microalgae spirulina (Spirulina platensis) in the diet of Gilthead Sea bream (Sparus aurata) on growth and metabolism

In gilthead seabream aquaculture, the feed supplies in the market is very expensive due to its high content of animal protein. In this respect, spiruline appears to be a valuable substitute to animal and vegetable protein. In this study we performed two experiments. The scope of the first one was to determine the effect of the inclusion of Spirulina platensis hydrolyzed on the physiological state and growth in juveniles of Sparus aurata. A total of 180 individuals were fed for 128 days with three different feeds: control diet, diet with 2% of hydrolyzed microalgae (Sp2), and diet with 4% of hydrolyzed microalgae (Sp4).The experimental groups were tested in triplicate (except control group that was in duplicate). Biometric parameters were registered every two or three weeks. At the end of the experiment blood samples were collected to analyze plasma metabolites. After this we tried to evaluate the anti-oxidant response in animals remained from the first experiment using a toxicological assay with sodium nitrite lasting three days. Fish were divided into control, Spi 2% and Spi 4%, all them with and without NaNO2. Even then, the plasma metabolites data were collected after 24h and 72h. At the end of the first experiment the administration of S. platensis appeared to have a negative impact on growth of S. aurata respect the control feed. Furthermore, the lactate content registered showed a significant difference between the control and the spiruline administration. In the second experiment the spiruline feed showed a glucose and a lactate content with significant differences after 72h of exposition to nitrites respect the control group due to the interaction between nitrites and treatment. S. platensis hydrolyzed 2% and 4% do not seems a good substitution for S. aurata both as a growth enhancer and improver of health metabolic pathways. Its role as a good antioxidant has not been confirmed in these experiments.

Study of the effectiveness of crystal growth modifiers in the prevention of damage due to crystallization of sodium carbonates in stone artworks

The disintegration of stone materials used in sculpture and architecture due to the crystallization of salts is capable of irreparably damaging artistic objects and historic buildings. A number of phosphonates and carboxylates were tested here as potential crystallization modifiers for sodium carbonate crystallization. Precipitated phases during crystallization induced either by cooling or by evaporation tests were nahcolite (NaHCO3), natron (Na2CO3∙10H2O) and thermonatrite (Na2CO3∙H2O), identified using X-ray diffraction. By using the thermodynamic code PHREEQC and the calculation of the nucleation rate it was demonstrated that nahcolite had to be first phase formed during both tests. The formation of the other phases depended on the experimental conditions under which the two tests were conducted. Nahcolite nucleation is strongly inhibited in the presence of sodium citrate tribasic dihydrate (CA), polyacrylic acid 2100MW (PA) and etidronic acid (HEDP), when the additives are dosed at appropriate concentrations and the pH range of the resulting solution is about 8. Electrostatic attraction generated between the deprotonated organic additives and the cations present in solution appears to be the principal mechanism of additive-nahcolite interaction. Salt weathering tests, in addition to mercury intrusion porosimetry tests allowed to quantify the damage induced by such salts. FESEM observation of both salts grown on calcite single crystals and in limestone blocks subjected to salt crystallization tests allowed to identify the effect of these additives on crystal growth and development. The results show that PA seems to be the best inhibitor, while CA and HEDP, which show similar behaviors, are slightly less effective. The use of such effective crystallization inhibitors may lead to more efficient preventive conservation of ornamental stone affected by crystallization damage due to formation of sodium carbonate crystals.

Incompressible limit and well-posedness of PDE models of tissue growth

Both compressible and incompressible porous medium models are used in the literature to describe the mechanical aspects of living tissues. Using a stiff pressure law, it is possible to build a link between these two different representations. In the incompressible limit, compressible models generate free boundary problems where saturation holds in the moving domain. Our work aims at investigating the stiff pressure limit of reaction-advection-porous medium equations motivated by tumor development. Our first study concerns the analysis and numerical simulation of a model including the effect of nutrients. A coupled system of equations describes the cell density and the nutrient concentration and the derivation of the pressure equation in the stiff limit was an open problem for which the strong compactness of the pressure gradient is needed. To establish it, we use two new ideas: an L3-version of the celebrated Aronson-Bénilan estimate, and a sharp uniform L4-bound on the pressure gradient. We further investigate the sharpness of this bound through a finite difference upwind scheme, which we prove to be stable and asymptotic preserving. Our second study is centered around porous medium equations including convective effects. We are able to extend the techniques developed for the nutrient case, hence finding the complementarity relation on the limit pressure. Moreover, we provide an estimate of the convergence rate at the incompressible limit. Finally, we study a multi-species system. In particular, we account for phenotypic heterogeneity, including a structured variable into the problem. In this case, a cross-(degenerate)-diffusion system describes the evolution of the phenotypic distributions. Adapting methods recently developed in the context of two-species systems, we prove existence of weak solutions and we pass to the incompressible limit. Furthermore, we prove new regularity results on the total pressure, which is related to the total density by a power law of state.

Unibo-BP: an innovative free software implementation of Bundle Protocol Version 7 (RFC 9171)

The BP (Bundle Protocol) version 7 has been recently standardized by IETF in RFC 9171, but it is the whole DTN (Delay-/Disruption-Tolerant Networking) architecture, of which BP is the core, that is gaining a renewed interest, thanks to its planned adoption in future space missions. This is obviously positive, but at the same time it seems to make space agencies more interested in deployment than in research, with new BP implementations that may challenge the central role played until now by the historical BP reference implementations, such as ION and DTNME. To make Unibo research on DTN independent of space agency decisions, the development of an internal BP implementation was in order. This is the goal of this thesis, which deals with the design and implementation of Unibo-BP: a novel, research-driven BP implementation, to be released as Free Software. Unibo-BP is fully compliant with RFC 9171, as demonstrated by a series of interoperability tests with ION and DTNME, and presents a few innovations, such as the ability to manage remote DTN nodes by means of the BP itself. Unibo-BP is compatible with pre-existing Unibo implementations of CGR (Contact Graph Routing) and LTP (Licklider Transmission Protocol) thanks to interfaces designed during the thesis. The thesis project also includes an implementation of TCPCLv3 (TCP Convergence Layer version 3, RFC 7242), which can be used as an alternative to LTPCL to connect with proximate nodes, especially in terrestrial networks. Summarizing, Unibo-BP is at the heart of a larger project, Unibo-DTN, which aims to implement the main components of a complete DTN stack (BP, TCPCL, LTP, CGR). Moreover, Unibo-BP is compatible with all DTNsuite applications, thanks to an extension of the Unified API library on which DTNsuite applications are based. The hope is that Unibo-BP and all the ancillary programs developed during this thesis will contribute to the growth of DTN popularity in academia and among space agencies.

An Efficient Protocol For The Generation Of Monocyte Derived Dendritic Cells Using Serum-free Media For Clinical Applications In Post Remission Aml Patients.

Protocols for the generation of dendritic cells (DCs) using serum as a supplementation of culture media leads to reactions due to animal proteins and disease transmissions. Several types of serum-free media (SFM), based on good manufacture practices (GMP), have recently been used and seem to be a viable option. The aim of this study was to evaluate the results of the differentiation, maturation, and function of DCs from Acute Myeloid Leukemia patients (AML), generated in SFM and medium supplemented with autologous serum (AS). DCs were analyzed by phenotype characteristics, viability, and functionality. The results showed the possibility of generating viable DCs in all the conditions tested. In patients, the X-VIVO 15 medium was more efficient than the other media tested in the generation of DCs producing IL-12p70 (p=0.05). Moreover, the presence of AS led to a significant increase of IL-10 by DCs as compared with CellGro (p=0.05) and X-Vivo15 (p=0.05) media, both in patients and donors. We concluded that SFM was efficient in the production of DCs for immunotherapy in AML patients. However, the use of AS appears to interfere with the functional capacity of the generated DCs.

Impaired Compensatory Beta-cell Function And Growth In Response To High-fat Diet In Ldl Receptor Knockout Mice.

In this study, we investigated the effect of low density lipoprotein receptor (LDLr) deficiency on gap junctional connexin 36 (Cx36) islet content and on the functional and growth response of pancreatic beta-cells in C57BL/6 mice fed a high-fat (HF) diet. After 60 days on regular or HF diet, the metabolic state and morphometric islet parameters of wild-type (WT) and LDLr-/- mice were assessed. HF diet-fed WT animals became obese and hypercholesterolaemic as well as hyperglycaemic, hyperinsulinaemic, glucose intolerant and insulin resistant, characterizing them as prediabetic. Also they showed a significant decrease in beta-cell secretory response to glucose. Overall, LDLr-/- mice displayed greater susceptibility to HF diet as judged by their marked cholesterolaemia, intolerance to glucose and pronounced decrease in glucose-stimulated insulin secretion. HF diet induced similarly in WT and LDLr-/- mice, a significant decrease in Cx36 beta-cell content as revealed by immunoblotting. Prediabetic WT mice displayed marked increase in beta-cell mass mainly due to beta-cell hypertrophy/replication. Nevertheless, HF diet-fed LDLr-/- mice showed no significant changes in beta-cell mass, but lower islet-duct association (neogenesis) and higher beta-cell apoptosis index were seen as compared to controls. The higher metabolic susceptibility to HF diet of LDLr-/- mice may be explained by a deficiency in insulin secretory response to glucose associated with lack of compensatory beta-cell expansion.

Genetic Predictors Of Long-term Response To Growth Hormone (gh) Therapy In Children With Gh Deficiency And Turner Syndrome: The Influence Of A Socs2 Polymorphism.

There is great interindividual variability in the response to GH therapy. Ascertaining genetic factors can improve the accuracy of growth response predictions. Suppressor of cytokine signaling (SOCS)-2 is an intracellular negative regulator of GH receptor (GHR) signaling. The objective of the study was to assess the influence of a SOCS2 polymorphism (rs3782415) and its interactive effect with GHR exon 3 and -202 A/C IGFBP3 (rs2854744) polymorphisms on adult height of patients treated with recombinant human GH (rhGH). Genotypes were correlated with adult height data of 65 Turner syndrome (TS) and 47 GH deficiency (GHD) patients treated with rhGH, by multiple linear regressions. Generalized multifactor dimensionality reduction was used to evaluate gene-gene interactions. Baseline clinical data were indistinguishable among patients with different genotypes. Adult height SD scores of patients with at least one SOCS2 single-nucleotide polymorphism rs3782415-C were 0.7 higher than those homozygous for the T allele (P < .001). SOCS2 (P = .003), GHR-exon 3 (P= .016) and -202 A/C IGFBP3 (P = .013) polymorphisms, together with clinical factors accounted for 58% of the variability in adult height and 82% of the total height SD score gain. Patients harboring any two negative genotypes in these three different loci (homozygosity for SOCS2 T allele; the GHR exon 3 full-length allele and/or the -202C-IGFBP3 allele) were more likely to achieve an adult height at the lower quartile (odds ratio of 13.3; 95% confidence interval of 3.2-54.2, P = .0001). The SOCS2 polymorphism (rs3782415) has an influence on the adult height of children with TS and GHD after long-term rhGH therapy. Polymorphisms located in GHR, IGFBP3, and SOCS2 loci have an influence on the growth outcomes of TS and GHD patients treated with rhGH. The use of these genetic markers could identify among rhGH-treated patients those who are genetically predisposed to have less favorable outcomes.