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•Use of different precursors in the metal-free polymeric carbon nitrides (PCNs) synthesis to control structural defects.•Amoxicillin photodegradation under visible light catalyzed by ...metal-free PCNs.•Investigation of the influence of the structural defects on PCNs amoxicillin photodegradation.•More defective PCNs are more active on amoxicillin photodegradation.•Low-cost and metal-free PCNs potential photocatalysts to industrial applications using solar light.
Herein, the structural defects of metal-free polymeric carbon nitrides were controlled by making use of different precursors in their syntheses, i.e. melamine (CN-M) and thiourea (CN-T), as well as a 1:1 mixture of them (CN-1M:1 T). By controlling the structural defects, the electronic, morphological and chemical properties were modified. Additionally, the activities of synthesized PCNs were evaluated for amoxicillin photodegradation under visible light irradiation (16 mW cm–2). The results of photocatalytic tests showed that CN-T material has better efficiency (100 % removal within 48 h), which is directly related to the greater number of defects present in its structure with consequent improvement of electron-hole pairs separation efficiency. The CN-T material showed excellent stability with only 13 % decrease in its photocatalytic activity after the third cycle. A mechanism for amoxicillin degradation by CN-T was proposed based on the ESI-MS and the in situ EPR allied with spin trapping method investigations.
The entorhinal cortex (EC) is associated with impaired cognitive function such as in the case of Alzheimer's disease, Parkinson's disease and Huntington's disease. The present study provides a ...detailed analysis of the cytoarchitectural and myeloarchitectural organization of the EC in the common marmoset Callithrix jacchus. Data were collected using Nissl and fiber stained preparations, supplemented with acetylcholinesterase and parvalbumin immunohistochemistry. The EC layers and subfields in the marmoset seem to be architectonically similar to those that have been proposed in nonhuman primates and humans to date; however, slight differences could be revealed using the present techniques. Throughout its rostrocaudal length, the entorhinal cortex presents a clear six‐layered pattern. The entorhinal cortex is divided into six fields, named mainly in accordance to their rostrocaudal and mediolateral positions. At rostral levels, the neurons tend to be organized in patches that are surrounded by large, thick, radially oriented bundles of fibers, and the deep layers are poorly developed. At caudal levels, the divisions are more laminated in appearance. AChE staining at the borders of adjacent fields are consistent with the changes in layering revealed in Nissl‐stained sections, of which the lateral regions of the EC display denser AChE staining than that of the medial banks. PV immunoreactivity was found in the labeled somata, dendrites, and axons in all layers and subdivisions. Additionally, we distinguished three subtypes of PV‐immunoreactive neurons: multipolar, bipolar and spherical‐shaped neurons, based on the shape of the somata and the disposition of the dendrites.
We provide a detailed analysis of the cytoarchitecture, myeloarchitecture and neurochemical considerations about the organization of the entorhinal cortex in the common marmoset (Callithrix jacchus). Variations of the basic lamination patterns permit the delineation of six different areas in the Entorhinal cortex.
Dam break problems occur in a variety of applications. In the present paper we are especially concerned with the mining industry, where a dam break can be a catastrophic event with significant harm ...to the environment. In this case, the materials involved have a yield stress property, i.e., they flow only when a threshold is overcome by the stress that acts on the material. The plastic number, which measures the importance of the yield stress in the overall characteristic stress, is the main dimensionless number analyzed, and carbopol solutions are the kind of material employed. Since slip is common in motions of yield stress materials, the influence of this phenomenon is investigated by a comparison between the flow over a smooth and a rough surface. An image processing that captures the evolution of the shape of the interface as well as particle image velocimetry measurements were employed as tools to understand the role played by the plastic number in the problem. A number of cases presented a triangular depression that originated from a difference between the flow below the initial yield surface position and a rigid body motion above the initial surface position.
Summary
To evaluate the level and factors affecting control of diabetes and cardiovascular risk factors in type 2 diabetes (TYPE 2 DM) patients. Multicentre cross‐sectional study: a sample of 430 ...primary care practices across Spain selected 1907 type 2 diabetic patients. The first five consecutive ambulatory patients with TYPE 2 DM were eligible for the inclusion into the survey. Patients were free of known cardiovascular disease (CVD). Control criteria were defined based on 2002 American Diabetes Association (ADA) clinical practice recommendations. A total of 1907 patients (51% women) aged 63 ± 9 years. Smoking prevalence was 22.6%, 50.6% had levels of A1c < 7%. Mean blood pressure (BP) was 148 ± 17/86 ± 10 mmHg. Only 7.8% have achieved the target of BP < 130/80 mmHg. Among the 1180 patients (65%) treated for hypertension, this target was attained in only 4.4% of patients. A measurement for low‐density lipoprotein (LDL) cholesterol was available in 1669 patients (88%). Only 5.9% of patients achieved the target of LDL < 100 mg/dl. Among the 638 patients (41.6%) on drug treatment for dyslipidaemia, this target was attained in only 5.6% of patients. Among type 2 diabetic patients in Spain the prevalence of cardiovascular risk factors is high. Control of glycaemia, smoking, BP and LDL are far from optimal despite the widespread use of guidelines for the management of diabetes and CVD. The application of published recommendations needs to be reinforced.
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•The niobic acid HY-340 was thermally modified at 200 °C, 400 °C and 600 °C.•These materials were applied in the photocatalytic reduction of levulinic acid.•The best performance was ...obtained by the photocatalyst synthesized at 600 °C.•Oxygen vacancies were made in this same Nb2O5 and further improved its activity.•The properties of photocatalysts with and without vacancies were studied in depth.
After the discovery that commercial niobic acid (H0) is able to reduce the levulinic acid in value added molecules, H0 was thermally treated at 200 °C, 400 °C, and 600 °C, generating the niobium oxides H1, H2 and H3 and the photocatalytic improvement towards reduction was investigated. Although the higher temperatures significantly decreased the specific surface area, it was important to remove surface hydroxyl groups and create the T and TT-Nb2O5 phase mixture in H3 which were responsible for its best performance (36.4% of conversion and almost 99% of selectivity for reduced products). To further improve the H3 photoactivity, an identical synthesis was performed in H2 flow to produce oxygen vacancies in the structure of the new photocatalyst (H3OV). This simple modification method increased ∼7% of products yield, which is the best photocatalytic result obtained for pure niobium oxides so far, and proved that it is possible to significantly increase photocatalytic performance without laborious modifications. The electronic and structural differences between H3 and H3OV were investigated by XRD Rietveld refinement, EPR, HR-TEM, DRS and SAED analyses.
Although the primary physiological effects produced by scorpion toxins are already well known, most of the secondary molecular events following scorpion neurotoxins–ion channel interactions are ...poorly understood and described. For this reason, we used a proteomic approach to determine the changes in relative protein abundance in F11 mouse neuroblastoma cells treated with Cn2, the major β-toxin from the venom of the scorpion Centruroides noxius Hoffmann. Here we show that the relative abundance of 24 proteins changed after Cn2 treatment. Proteins related to protection from apoptosis and cell survival, as well as those involved in cell morphology and some translation elongation factors were diminished. By contrast, proteins associated with energy metabolism were increased. Additionally, results of western immunoblots confirmed the preference of action towards some special targets. These results suggest that Cn2 could modify the neuronal structure and induce apoptosis and reduction of the proliferation and cell survival. To support this conclusion we directly measured the Cn2 effect on cell proliferation, division and apoptosis. Our results open new avenues for continuing the studies aimed at better understanding the envenomation process caused by scorpion stings.
The purpose of this work was to identify which proteins, apart from the ion-channels, are involved in the envenomation process in order to develop possible strategies to circumvent the deleterious effects caused by the toxic peptides of the venom. For this reason, we characterized the early changes in the proteome of F11 cells induced by Cn2, the major toxin of the New World scorpion C. noxius Hoffmann, using 2D-PAGE and LC–MS/MS. We identified 24 proteins which relative abundance is modified after the Cn2 treatment. Among these, proteins related with apoptosis protection, cell survival, neuronal morphology and some translation elongation factors were diminished, whereas proteins associated with energy metabolism were increased.
This article is part of a Special Issue entitled: Proteomics, mass spectrometry and peptidomics, Cancun 2013. Guest Editors: César López-Camarillo, Victoria Pando-Robles and Bronwyn Jane Barkla.
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•Twenty-four proteins were modified by Cn2 treatment on neuroblastoma F11 cells.•Proteins related to apoptosis protection and neuronal morphology is decreased.•Proteins responsible for translation elongation factors are also diminished.•Proteins related with energy metabolism are increased.•Cn2 reduces the proliferation of F11 cells, induces apoptosis and cell cycle arrest.
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