Can a Soil Mineralization Test Improve Wheat and Corn Nitrogen Diagnosis?

A network of field studies determined that the traditional method for predicting soil N availability …a pre-plant nitrate test … can be combined with an indicator of soil N mineralization capacity to significantly improve the diagnosis for soil N availability for both wheat and corn.Fil: Reussi Calvo, Nahuel Ignacio. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Laboratiorio de Suelos. Fertilab; ArgentinaFil: Echeverría, Hector E.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Sainz Rozas, Hernan Rene. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Berardo, Angel. Laboratiorio de Suelos. Fertilab; ArgentinaFil: Diovisalvi, Natalia. Laboratiorio de Suelos. Fertilab; Argentin

Modelling the Excited State Properties of TiO2 Nanoparticles

Since the discovery in 1972 of photocatalytic water splitting on TiO2 electrodes, there has been a worldwide research effort focused on the study of this material. Recently, it was shown that the use of nanosized systems could overcome the usual TiO2 limitations, e.g. a too large band gap, and increase its efficiency in photocatalytic applications. This thesis involves the computational modelling of excited state properties of TiO2 nanoparticles in order to provide atomic scale insights into the optical and photocatalytic properties of these materials. In the first part of this thesis, accurate correlated wave function benchmarks (i.e. EOM-CC) are defined for the calculation of excited states of small TiO2 nanoparticles (< 1 nm in size). These results are then employed for the evaluation of the accuracy of different Time Dependent DFT (TDDFT) exchange-correlation (XC) potentials. The main conclusion is that standard TDDFT XC energy functionals (e.g. PBE, B3LYP) tend to underestimate charge transfer excitations, whereas long-range corrected (e.g. CAM-B3LYP) potentials accurately describe optical properties of TiO2 nanoparticles. Following this study, in an effort to close the gap between simple theoretical models and systems of experimental relevance, TD-DFT is used for the investigation of a range of optical and excited state properties for a rutile bulk-like particle with a diameter of approximately 2 nm. These studies reveal that this or smaller rutile nanoparticles are predicted to be thermodynamically unable to drive photocatalytic water splitting because of the strong self-trapping of free electrons and holes generated during the excitation process in these particles. Finally, the excited state lifetimes and the photo-reactivity of a small hydrated TiO2 particle were investigated by employing TD-DFT non-adiabatic excited state molecular dynamics (NAMD). This study corresponds to a first attempt of using TD-DFT touncover the initial steps of the photochemical water-splitting reaction catalysed by TiO2 nanoparticles. The results from this thesis suggest that in the case of the TD-B3LYP trajectories, the first steps of the water splitting reaction mechanism are found to be heterolytic in character

Amine molecular cages as supramolecular fluorescent explosive sensors: a computational perspective

We investigate using a computational approach the physical and chemical processes underlying the application of organic (macro)molecules as fluorescence quenching sensors for explosives sensing. We concentrate on the use of amine molecular cages to sense nitroaromatic analytes, such as picric acid and 2,4-dinitrophenol, through fluorescence quenching. Our observations for this model system hold for many related systems. We consider the different possible mechanisms of fluorescence quenching: Förster resonance energy transfer, Dexter energy transfer and photoinduced electron transfer, and show that in the case of our model system, the fluorescence quenching is driven by the latter and involves stable supramolecular sensor–analyte host–guest complexes. Furthermore, we demonstrate that the experimentally observed selectivity of amine molecular cages for different explosives can be explained by the stability of these host–guest complexes and discuss how this is related to the geometry of the binding site in the sensor. Finally, we discuss what our observations mean for explosive sensing by fluorescence quenching in general and how this can help in future rational design of new supramolecular detection systems

Higher expression of vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 (Flk-1) and metalloproteinase-9 (MMP-9) in a rat model of peritoneal endometriosis is similar to cancer diseases

<p>Abstract</p> <p>Background</p> <p>Endometriosis is a common disease characterized by the presence of a functional endometrium outside the uterine cavity, causing pelvic pain, dysmenorrheal, and infertility. This disease has been associated to development of different types of malignancies; therefore new blood vessels are essential for the survival of the endometrial implant. Our previous observations on humans showed that angiogenesis is predominantly found in rectosigmoid endometriosis, a deeply infiltrating disease. In this study, we have established the experimental model of rat peritoneal endometriosis to evaluate the process of angiogenesis and to compare with eutopic endometrium.</p> <p>Methods</p> <p>We have investigated the morphological characteristics of these lesions and the vascular density, VEGF and its receptor Flk-1 and MMP-9 expression, and activated macrophage distribution, using immunohistochemistry and RT-PCR.</p> <p>Results</p> <p>As expected, the auto-transplantation of endometrium pieces into the peritoneal cavity is a well-established method for endometriosis induction in rats. The lesions were cystic and vascularized, and demonstrated histological hallmarks of human pathology, such as endometrial glands and stroma. The vascular density and the presence of VEGF and Flk-1 and MMP-9 were significantly higher in endometriotic lesions than in eutopic endometrium, and confirmed the angiogenic potential of these lesions. We also observed an increase in the number of activated macrophages (ED-1 positive cells) in the endometriotic lesions, showing a positive correlation with VEGF.</p> <p>Conclusion</p> <p>The present endometriosis model would be useful for investigation of the mechanisms of angiogenesis process involved in the peritoneal attachment of endometrial cells, as well as of the effects of therapeutic drugs, particularly with antiangiogenic activity.</p

Modelling the Water Splitting Activity of a TiO 2 Rutile Nanoparticle

We explore, from a theoretical perspective, the effect of particle size on the photocatalytic water splitting activity of TiO2 rutile (nano)particles by a combination of explicit quantum chemistry calculations on a hydroxylated rutile nanoparticle in a realistic solvation environment and a comparison with the calculated properties of bulk rutile (surfaces) from the literature. Specifically, we use density functional theory (DFT) and time-dependent DFT to calculate the nanoparticle thermodynamic driving force for the water splitting half-reactions and identify in the process the crucial role of self-trapping of the free charge carriers responsible for proton reduction and water oxidation

Structurally Diverse Covalent Triazine-based Framework Materials for Photocatalytic Hydrogen Evolution from Water

A structurally diverse family of 39 covalent triazine-based framework materials (CTFs) are synthesized by Suzuki–Miyaura polycondensation and tested as hydrogen evolution photocatalysts using a high-throughput workflow. The two best-performing CTFs are based on benzonitrile and dibenzo[b,d]thiophene sulfone linkers, respectively, with catalytic activities that are among the highest for this material class. The activities of the different CTFs are rationalized in terms of four variables: the predicted electron affinity, the predicted ionization potential, the optical gap, and the dispersibility of the CTFs particles in solution, as measured by optical transmittance. The electron affinity and dispersibility in solution are found to be the best predictors of photocatalytic hydrogen evolution activity

Subcutaneous Adipose Tissue Transcriptome Highlights Specific Expression Profiles in Severe Pediatric Obesity: A Pilot Study

The prevalence of pediatric obesity is rising rapidly worldwide, and "omic" approaches are helpful in investigating the molecular pathophysiology of obesity. This work aims to identify transcriptional differences in the subcutaneous adipose tissue (scAT) of children with overweight (OW), obesity (OB), or severe obesity (SV) compared with those of normal weight (NW). Periumbilical scAT biopsies were collected from 20 male children aged 1-12 years. The children were stratified into the following four groups according to their BMI z-scores: SV, OB, OW, and NW. scAT RNA-Seq analyses were performed, and a differential expression analysis was conducted using the DESeq2 R package. A pathways analysis was performed to gain biological insights into gene expression. Our data highlight the significant deregulation in both coding and non-coding transcripts in the SV group when compared with the NW, OW, and OB groups. A KEGG pathway analysis showed that coding transcripts were mainly involved in lipid metabolism. A GSEA analysis revealed the upregulation of lipid degradation and metabolism in SV vs. OB and SV vs. OW. Bioenergetic processes and the catabolism of branched-chain amino acids were upregulated in SV compared with OB, OW, and NW. In conclusion, we report for the first time that a significant transcriptional deregulation occurs in the periumbilical scAT of children with severe obesity compared with those of normal weight or those with overweight or mild obesity

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Abstract:&nbsp; Graves\u27 disease (GD) can be surgically treated and present complications like postoperative hypocalcemia. Objectives: (1) Evaluate the incidence of postoperative hypocalcemia in patients with GD. (2) Find out if hypocalcemia incidence is grater in thyroidectomized patients due to other causes. (3) Determine whether hypovitaminosis D is predictive of hypocalcemia. (4) Establish the usefulness of vitamin D (VD) substitution. We conducted an analytic longitudinal observational cohort study. We included 12 patients with GD (Graves group) and 23 thyroidectomized patients as a result of other benign thyroid diseases (BTD), both sexes, 18 to 70 years old. There was a total of 3 males (9%) and 32 females (91%). Preoperative calcemia was (: 9.1 ± 0.5 mg/dL). Postoperative calcemia was (: 8.6 ± 0.6 mg/dL) after 8 hours, (: 8.6 ± 0.6 mg/dL) after 12 hours, (: 8.9 ± 0.6 mg/dL) after 1 month and (: 9 ± 0.8 mg/dL) 6 months after surgery. Preoperative VD was (: 23.1 ± 10 ng/mL). Hypocalcemia was defined as calcemia &lt; 8.5 mg/dL. Transient calcemia was defined as less than 6 months. Permanent calcemia was defined as over 6 months. Within GD group, hypocalcemia incidence was 54.4% (6 patients) 8 hours after surgery, 45.5% (4 patients) 12 hours after surgery, 16.7% (2 patients) 1 month after surgery and 33% (4 patients) 6 months after surgery. Within BTD group, hypocalcemia incidence was 26.1% (6 patients) 8 hours after surgery, 26.1% (6 patients) 12 hours after surgery, 13% (3 patients) 1 month after surgery and 22% (5 patients) 6 months after surgery (p&gt;0.05). Preoperative VD in Graves group vs. BTD group (15.3 ± 4.5 ng/dl vs. 25.3 ± 10 ng/dl) (p&lt;0.05). With preoperative VD replacement, we observed that 70% of the patients (n:7) didn\u27t present postoperative hypocalcemia, while 30% (n:3) did. Without preoperative replacement, we observed that 40% of them (n:10) didn\u27t present hypocalcemia, while 60% (n:15) did. (p&gt;0.05). We noticed that patients with GD have a higher incidence of transient and permanent hypocalcemia than patients in the BTD group. Also, none within the GD group had enough preoperative VD; therefore, hypovitaminosis D might be a predictive factor for hypocalcemia. Although a larger sample is needed, considering sufficient preoperative VD levels would be advisable to avoid postoperative hypocalcemias.Resumen:&nbsp; La enfermedad de Graves (EG) puede ser tratada quirúrgicamente y presentar complicaciones como hipocalcemia postquirúrgica. Objetivos: 1-Evaluar incidencia de hipocalcemia post quirúrgica en pacientes con EG. 2-Conocer si la incidencia de hipocalcemia es mayor que en pacientes con tiroidectomías por otras causas. 3-Determinar si hipovitaminosis D es predictiva para hipocalcemias. 4-Establecer la utilidad de sustituir vitamina D (VD). Realizamos estudio observacional analítico longitudinal de cohorte. Incluimos 12 pacientes con EG (grupo Graves) y 23 tiroidectomizados por otras patologías tiroideas benignas (PTB), ambos sexos, 18-70 años. Total 3 masculinos (9%) y 32 femeninos (91%).&nbsp; Calcemia pre (x-: 9,1 ± 0,5 mg/dl) y post quirúrgica: 8 horas (x-: 8,6 ± 0,6 mg/dl), 12 horas (x-: 8,6 ± 0,6 mg/dl), al mes (x-: 8,9 ± 0,6 mg/dl) y 6 meses (x-: 9 ± 0.8 mg/dl) y VD prequirúrgica (x-: 23,1 ± 10 ng/ml). Definimos hipocalcemia: calcemia &lt; 8,5 mg/dL. Transitoria: menor 6 meses. Permanente: más de 6 meses. En grupo EG, la incidencia de hipocalcemia: a las 8 horas post cirugía 54,4% (6 pacientes), 12 horas 45,5% (4 pacientes), al mes 16,7% (2 pacientes) y a 6 meses 33% (4 pacientes). En grupo PTB, hipocalcemia: 8 horas postquirúrgica 26,1% (6 pacientes), 12 horas 26,1% (6 pacientes), al mes 13% (3 pacientes) y a los 6 meses 22% (5 pacientes) (p&gt;0,05). La VD prequirúrgica en grupo Graves vs. PTB (15,3 ± 4,5 ng/dl vs. 25,3 ± 10 ng/dl) (p&lt;0,05). Con sustitución prequirúrgica de VD observamos que el 70% de los pacientes (n:7) no presentaron hipocalcemia postquirúrgica, y si la presentó el 30% (n:3). En grupo sin sustitución prequirúrgica, no presentaron hipocalcemia el 40% (n:10), aunque sí lo hicieron el 60% (n:15) (p&gt;0.05). Observamos que pacientes con EG tienen mayor incidencia de hipocalcemia transitoria y permanente que el grupo PTB. A su vez, dentro del grupo EG, ninguno tuvo VD suficiente prequirúrgica, por lo que hipovitaminosis D podría ser un factor predictivo para hipocalcemia. Aunque se requiere mayor tamaño en la muestra, sería aconsejable niveles de VD suficientes prequirúrgicos para evitar hipocalcemias postquirúrgicas.

Bone Marrow Mesenchymal Stem Cells Expanded Inside the Nichoid Micro-Scaffold: a Focus on Anti-Inflammatory Response

Purpose Mesenchymal stem cells (MSCs) represent a promising source for stem cell therapies in numerous diseases, including pediatric respiratory system diseases. Characterized by low immunogenicity, high anti-inflammatory, and immunoregulatory features, MSCs demonstrated an excellent therapeutic profile in numerous in vitro and preclinical models. MSCs reside in a specialized physiologic microenvironment, characterized by a unique combination of biophysical, biochemical, and cellular properties. The exploitation of the 3D micro-scaffold Nichoid, which simulates the native niche, enhanced the anti-inflammatory potential of stem cells through mechanical stimulation only, overcoming the limitation of biochemical and xenogenic growth factors application.Materials and Methods In this work, we expanded pediatric bone marrow MSCs (BM-MSCs) inside the Nichoid and performed a complete cellular characterization with different approaches including viability assays, immunofluorescence analyses, RNA sequencing, and gene expression analysis.Results We demonstrated that BM-MSCs inside the scaffold remain in a stem cell quiescent state mimicking the condition of the in vivo environment. Moreover, the gene expression profile of these cells shows a significant up-regulation of genes involved in immune response when compared with the flat control.Conclusion The significant changes in the expression profile of anti-inflammatory genes could potentiate the therapeutic effect of BM-MSCs, encouraging the possible clinical translation for the treatment of pediatric congenital and acquired pulmonary disorders, including post-COVID lung manifestations

Redox Imbalance in Neurological Disorders in Adults and Children

Oxygen is a central molecule for numerous metabolic and cytophysiological processes, and, indeed, its imbalance can lead to numerous pathological consequences. In the human body, the brain is an aerobic organ and for this reason, it is very sensitive to oxygen equilibrium. The consequences of oxygen imbalance are especially devastating when occurring in this organ. Indeed, oxygen imbalance can lead to hypoxia, hyperoxia, protein misfolding, mitochondria dysfunction, alterations in heme metabolism and neuroinflammation. Consequently, these dysfunctions can cause numerous neurological alterations, both in the pediatric life and in the adult ages. These disorders share numerous common pathways, most of which are consequent to redox imbalance. In this review, we will focus on the dysfunctions present in neurodegenerative disorders (specifically Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis) and pediatric neurological disorders (X-adrenoleukodystrophies, spinal muscular atrophy, mucopolysaccharidoses and Pelizaeus-Merzbacher Disease), highlighting their underlining dysfunction in redox and identifying potential therapeutic strategies