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Point defects play important and crucial roles in the design of high performance photocatalysts. We report on the electrochemical fabrication of black Ti−Mo-Ni−O nanotubes as a promising electrode material for solar-assisted water splitting. The ternary Ti−Mo-Ni−O catalyst was annealed in hydrogen atmosphere to induce point defects in the material to enhance its conductivity, charge carriers density, and performance. The effect of annealing duration on the performance of ternary Ti−Mo-Ni−O nanotube films was investigated. The hydrogen-annealed nanotubes showed enhanced optical characteristics in the visible spectrum, which can be related to the formation of defect states upon hydrogen annealing. The 10 h-annealed sample showed an exceptionally enhanced photocurrent density of ∼10 mA/cm2 with a remarkable open-circuit voltage of ∼−1.0 VAg/AgCl under AM 1.5G illumination. This improved photocurrent is in agreement with the obtained 75 % incident-photon-to-current-conversion-efficiency (IPCE), confirming the improved photoactivity of the hydrogen-treated mixed oxide nanotubes.

A new strain of coronavirus, called SARS-CoV-2, emerged in Wuhan, China, in December 2019, probably originating from a wild-animal contamination. Since then, the situation rapidly evolved from a cluster of patients with pneumonia, to a regional epidemic and now to a pandemic called COrona VIrus Disease 2019 (COVID-19). This evolution is related to the peculiar modes of transmission of the disease and to the globalization and lifestyle of the 21st century that created the perfect scenario for virus spread. Even though research has not evidenced particular susceptibility of inflammatory bowel disease (IBD) patients to SARS-CoV-2 infection, immunosuppressive and immunomodulatory treatments were considered potential risk factors. In this context, initiating treatments with these agents should be cautiously weighted and regular ongoing treatments shall be continued, while the dose of corticosteroids should be reduced whenever possible. Due to the increased risk of contamination, elective endoscopic procedures and surgeries should be postponed and IBD online appointments shall be considered. IBD patients shall also follow the recommendations provided to the general population, such as minimization of contact with infected or suspected patients and to wash hands frequently. In the absence of effective treatments and vaccines, this pandemic can only be controlled through prevention of SARS-CoV-2 transmission with the main objectives of providing patients the best healthcare possible and reduce mortality.

This study focused on the development and characterization of biodegradable films based on gelatin capsule residue crosslinked with the natural agent genipin extracted from genipap (Genipa americana L.). Their potential on maintaining the quality attributes (level of peroxides, conjugated dienes and trienes and color) of extra‐virgin olive oil under accelerated storage conditions was investigated. Results showed that the genipin‐crosslinked films had a dark blue appearance. Their total soluble matter, water vapor permeability, tensile strength, ultraviolet and visible light barriers and thermal properties were improved in relation to the uncrosslinked film, whereas their moisture content and microstructure were not affected. In general, films presented comparable properties to those of glutaraldehyde‐crosslinked films. The developed films successfully protected the packed oil from primary and secondary oxidation and maintained the color over the storage period. Therefore, this study demonstrated the effectiveness of genipin on improving the properties of gelatin‐based films and the promising application of films as food packaging.

The molecular structures of CaO–FeOₓ–SiO₂ slags and their inorganic polymer counterparts were determined using neutron and X‐ray scattering with subsequent pair distribution function (PDF) analysis. The slags were synthesized with approximate molar compositions: 0.17CaO–0.83FeO–SiO₂ and 0.33CaO–0.67FeO–SiO₂ (referred to as low‐Ca and high‐Ca, respectively). The PDF data on the slags reasserted the predominantly glassy nature of this iron‐rich industrial byproduct. The dominant metal‐metal correlation was Fe–Si (3.20‐3.25 Å), with smaller contributions from Fe–Ca (3.45‐3.50 Å) and Fe–Fe (2.95‐3.00 Å). After inorganic polymer synthesis, a rise in the amount of Fe³⁺ was observed via the shift of the Fe–O bond length to shorter distances. This shortening of the Fe–O distance in the binder is also evidenced by the apparent rise of the Fe–Fe correlation at 2.95‐3.00 Å, although this feature may also suggest a potential aggregation of FeOₓ clusters. In general, the atomic arrangements of the reaction product was shown to be very similar to the precursor structure and the dominance of the Fe–Si correlation suggests the participation of Fe in the silicate network. The binder was shown to be glassy, as no distinct atom‐atom correlations were observed beyond 8 Å. ispartof: JOURNAL OF THE AMERICAN CERAMIC SOCIETY vol:101 issue:12 pages:5846-5857 status: Published online

International audience; The influence of N concentration on the crystallization kinetics, microstructural evolution, and composition of Ge‐rich GeSbTe (GGST) alloys during thermal annealing, using X‐ray diffraction and scanning and transmission electron microscopy is reported. It is shown that the incorporation of N in GGST tends to slow down the phase separation, crystallization, and growth processes during annealing. This can be attributed to the reduced diffusivity of Ge, which interacts and quickly bonds with N. Technological advantages of N doping are also discussed, considering the increased stability of the amorphous phase with respect to its parent crystalline phase, finer microstructure, flatness of the GeSbTe (GST) films after crystallization, and disappearance of the low‐resistivity hexagonal phase at high temperature.

Thiol-isocyanate chemistry, combined with a dual capsule strategy, is used for the development of extrinsic self-healing epoxy materials. It is shown that the amine groups present in the matrix both serve as a catalyst for the addition reaction between a thiol and an isocyanate and as a way to covalently link the healed network structure to the surrounding resin. The tapered double cantilever beam (TDCB) geometry is used for evaluating the recovery of the fracture toughness at room temperature after different healing times. Using manual injection of the healing agents into the crack, a healing efficiency up to 130% is obtained for the EPIKOTE 828/DETA epoxy material. On the other hand, when two types of microcapsules, one containing a tetrathiol reagent and the other a low toxic isocyanate reagent, are incorporated into this epoxy thermoset (20 wt%), a recovery of more than 50% is reached. The influence of parameters such as the amount and core content of the microcapsules on the healing efficiency is investigated. Furthermore, the thiol-isocyanate chemistry is also tested for an industrial cold-curing epoxy resin (RIM 135/RIMH 137).

Objective: Congenital hyperinsulinism (CHI) requires rapid diagnosis and treatment to avoid irreversible neurological sequelae due to hypoglycaemia. Aetiological diagnosis is instrumental in directing the appropriate therapy. Current diagnostic algorithms provide a complete set of diagnostic tools including (i) biochemical assays, (ii) genetic facility and (iii) state-of-the-art imaging. They consider the response to a therapeutic diazoxide trial an early, crucial step before proceeding (or not) to specific genetic testing and eventually imaging, aimed at distinguishing diffuse vs focal CHI. However, interpretation of the diazoxide test is not trivial and can vary between research groups, which may lead to inappropriate decisions. Objective of this report is proposing a new algorithm in which early genetic screening, rather than diazoxide trial, dictates subsequent clinical decisions. Patients, Methods and Results: Two CHI patients weaned from parenteral glucose infusion and glucagon after starting diazoxide. No hypoglycaemia was registered during a 72-h continuous glucose monitoring (CGMS), or hypoglycaemic episodes were present for no longer than 3% of 72-h. Normoglycaemia was obtained by low–medium dose diazoxide combined with frequent carbohydrate feeds for several years. We identified monoallelic, paternally inherited mutations in KATP channel genes, and 18F-DOPA PET-CT revealed a focal lesion that was surgically resected, resulting in complete remission of hypoglycaemia. Conclusions: Although rare, some patients with focal lesions may be responsive to diazoxide. As a consequence, we propose an algorithm that is not based on a ‘formal’ diazoxide response but on genetic testing, in which patients carrying paternally inherited ABCC8 or KCNJ11 mutations should always be subjected to 18F-DOPA PET-CT.

PCL/chitosan blend nanofibres could provide an excellent nanostructured material for biomedical use since their beneficial properties are combined into one material. This paper focuses on the solvent use in the production of PCL/chitosan nanofibres by solution electrospinning, since this is a crucial parameter in the electrospinning process. It was established that an acetic acid/formic acid shows great potential for the stable electrospinning of the blend. Additionally, the fibre morphology using this solvent system was analysed.

International audience; Mild & green: The commercially and readily available PNPCl behaves as a very effective catalyst for the synthesis of various trimethylsilyl cyanohydrins from a wide range of aliphatic, cyclic, α,β-unsaturated and aromatic ketones. The method proceeds at room temperature in solvent-free conditions, in the presence of very small amounts of catalyst (see scheme).

Background Involvement of the lymphatic system in inflammatory bowel disease (IBD) has been suggested. Aims To examine the density and distribution of lymphatic vessels (LV) within inflamed and non-inflamed wall sections of IBD patients compared with controls, and to evaluate expression of major lymphangiogenic factors. Methods Ileal and colon specimens of 22 patients with Crohn’s disease (CD), 16 patients with ulcerative colitis (UC) and 11 controls were studied. Quantification of LV was performed using immunohistochemistry with podoplanin and D2-40 antibodies on seven randomly selected fields. Mucosal expression of podoplanin and lymphangiogenic factor mRNA was measured using PCR. Results In CD patients, lymphatic density was significantly increased in noninflamed and inflamed ileal (P < 0.01 and P < 0.001) and colonic (P < 0.01 and P < 0.001) mucosa compared to controls. Podoplanin mRNA levels were similar in non-inflamed mucosal areas and controls, whereas a fourand sixfold increase was seen in inflamed ileal and colonic areas (P < 0.05). In UC, lymphatic density increased fourfold in non-inflamed (P < 0.001) and fivefold in inflamed colonic mucosa (P < 0.001) compared with controls. An increase in podoplanin mRNA levels was seen in both noninflamed and inflamed areas (P < 0.01) compared with controls. In CD and UC, lymphatics were found throughout the inflamed mucosa, including the upper half of the lamina propria. Expression of lymphangiogenic factors was similar in patients and controls. Conclusions Increased density of lymphatic vessels is a constant feature of IBD and is present in non-inflamed areas. It is transmural in CD and confined to the mucosa in UC. Its origin remains unclear

Pleistocene glacial and interglacial periods have moulded the evolutionary history of European cold-adapted organisms. The role of the different mountain massifs has, however, not been accurately investigated in the case of high-altitude insect species. Here, we focus on three closely related species of non-flying leaf beetles of the genus Oreina (Coleoptera, Chrysomelidae), which are often found in sympatry within the mountain ranges of Europe. After showing that the species concept as currently applied does not match barcoding results, we show, based on more than 700 sequences from one nuclear and three mitochondrial genes, the role of biogeography in shaping the phylogenetic hypothesis. Dating the phylogeny using an insect molecular clock, we show that the earliest lineages diverged more than 1 Mya and that the main shift in diversification rate occurred between 0.36 and 0.18 Mya. By using a probabilistic approach on the parsimony-based dispersal/vicariance framework (MP-DIVA) as well as a direct likelihood method of state change optimization, we show that the Alps acted as a cross-roads with multiple events of dispersal to and reinvasion from neighbouring mountains. However, the relative importance of vicariance vs. dispersal events on the process of rapid diversification remains difficult to evaluate because of a bias towards overestimation of vicariance in the DIVA algorithm. Parallels are drawn with recent studies of cold-adapted species, although our study reveals novel patterns in diversity and genetic links between European mountains, and highlights the importance of neglected regions, such as the Jura and the Balkanic range.

Patients treated with infliximab for Crohn's disease (CD) frequently require intensified dosage due to loss of response. There are scant data regarding the efficacy of shortening the dosing interval to 6 weeks.

I mostly focus on Clarke's point that the “old African diaspora” and the “new African diaspora” are grounded on different ontologies. I show that even though I have great sympathy for her larger argument, the separation between old and new diasporas runs the risk of appearing somewhat simplistic and even perhaps unrealistic. I conclude with the assertion that if it is true that contemporary African states have engaged in the production and circulation of “new narratives of diaspora,” it is not less true that the same states also manipulate—particularly in sites of memory in West African contexts—older narratives centered on the trans-Atlantic slave trade.

We report the case of a 35-year-old man who contracted vitamin A-induced liver cirrhosis. Five years before, he had been investigated for vitamin A-induced non-cirrhotic portal hypertension. In this case, the clinical and histopathologic evolution from non-cirrhotic portal hypertension to cirrhosis was documented. In spite of the cessation of pharmaceutical vitamin A intake, the disease progressed. Therapy with colchicine and phenobarbital apparently did not influence evolution to cirrhosis. This suggests that vitamin A can trigger largely unknown mechanisms of liver fibrosis which seem to be self-perpetuating.

The cytochrome P-450 3A family is involved in the metabolism of several drugs, including nifedipine, cyclosporine, quinidine and erythromycin. The purpose of this study was to develop a reliable method to obtain a relative quantification of cytochrome P-450 3A apoproteins in rat liver specimens by immunocytochemistry and to correlate such quantification to erythromycin N-demethylase activity, a biochemical pathway sustained by that enzymatic system. Thirty-six male Wistar rats were treated with an injection of either saline or dexamethasone phosphate (10, 30 or 50 mg/kg), a potent inducer of cytochrome P-450 3A. Specimens taken from the same lobe were processed for immunocytochemistry and determination of erythromycin N-demethylase activity. Paraffin sections were treated with a polyclonal antiserum directed against cytochrome P-450 3A. The density of cytochrome P-450 3A immunostaining measured by an automatic image analyzer increased with the dose of dexamethasone pretreatment, and with the erythromycin N-demethylase activity, both parameters being closely correlated. Our data indicate that in rats, when cytochrome P-450 3A is concerned, there is a close correlation between the results of immunoquantitation and biochemical activity. This suggests that such a method of investigation might be used on small paraffin-embedded liver specimens obtained by needle biopsy.

A 52-year-old man, having been treated for 4 months with chlorpropamide for diabetes mellitus type II, developed severe cholestatic hepatitis following a short course of erythromycin ethylsuccinate. Despite prompt withdrawal of both drugs, the cholestatic picture worsened and was associated with morphological evidence of disappearing interlobular bile ducts. After a 2-year course of profound cholestasis complicated by steatorrhea and striking hyperlipidemia, the patient died of ischemic cardiomyopathy. It is believed that this is the first published case of irreversible cholestasis with disappearance of ducts potentially related to a metabolic interaction between erythromycin ethylsuccinate and chlorpropamide.

As evidenced by the series of commentaries that followed the good performance of the Ecuadorian soccer team at the 2006 Mundial, which I discuss in the last section of this essay, the place of blackness within/outside Ecuadorian national identity continues to be ambiguous despite the multicultural turn formally officialized with the adoption of the 1998 Constitution. Through the analysis of visual representations of Afro-Ecuadorian men, I sketch the long history of black exclusion from the dominant Ecuadorian understanding of the nation during monocultural mestizaje, and the metamorphosis of this exclusion into multiculturalism. This provides a genealogy for today's spontaneous representations of Ecuadorian black athletes found on the internet and on the daily press. As indicated by the essay's title, I conclude that even though notable changes have occurred since the “multicultural turn,” there are also profound ideological continuities. I argue that in fact with multiculturalism, mestizaje—as an ideological technology of the state and as a project of the Ecuadorian elites—has not disappeared from the political landscape but instead continues to do its work both within and around multiculturalism. Thus, for Afro-Ecuadorians, the passage of the official or national stance from “monocultural mestizaje” to “multiculturalism” has not been accompanied by the transformations that the change of vocabulary might suggest. Instead, it has reinscribed the prevalent racial order in a “new” narration of the nation.

Making Ecuadorian Histories: Four Centuries of Defining Power. O. Hugo Benavides, Austin: University of Texas Press, 2004. 231 pp.

RNA-mediated gene silencing (RNA interference) is a powerful way to knock down gene expression and has revolutionized the fields of cellular and molecular biology. Indeed, the transfection of cultured cells with small interfering RNAs (siRNAs) is currently considered to be the best and easiest approach to loss-of-function experiments. However, several recent studies underscore the off-target and potential cytotoxic effects of siRNAs, which can lead to the silencing of unintended mRNAs. In this study, we used a low-density microarray to assess gene expression modifications in response to five different siRNAs in various cell types and transfection conditions. We found major differences in off-target signature according to: (a) siRNA sequence; (b) cell type; (c) duration of transfection; and (d) post-transfection time before analysis. These results contribute to a better understanding of important parameters that could impact on siRNA side effects in knockdown experiments.

AIMS: This report describes three patients suffering from nodular regenerative hyperplasia (NRH). METHODS: These patients have received six, 16 and 20 cycles of neoadjuvant 5-fluorouracil and oxaliplatin-based chemotherapy before planned extended hepatectomy. Two patients underwent uneventful portal vein embolization to hypertrophy the future remnant liver. RESULTS: At the end of chemotherapy, liver function tests deteriorated and portal hypertension appeared in two patients, including ascites, splenomegaly and oesophageal varices. Liver biopsy was performed through a percutaneous (two patients) or a transjugular approach (one patient) and allowed the diagnosis of NRH, which was considered to be a contraindication for major liver resection in all three patients, associated with extrahepatic disease progression in one patient. All patients died from neoplastic disease progression despite further chemotherapy at 6, 17 and 31 months following the diagnosis of NRH. One patient developed liver failure and ascites at the time of death. CONCLUSIONS: Physicians should be aware of the potential occurrence and therapeutic impact of NRH in patients suffering from CRLM and treated by neoadjuvant 5FU-oxaliplatin-based chemotherapy before major liver surgery.

Dye–fiber interactions are studied in poly (ethylene terephthalate) fibers by FT-IR spectroscopy. It is shown for the first time that DRIFTS (diffuse reflectance infrared Fourier transform spectroscopy) serves as an easy applicable and accurate technique for the study of fibrous structures. This article focuses on the possible hydrogen bond interactions in the dye–fiber system, where the PET fibers are dyed with anthraquinone-based disperse dyes. The dyes and related anthraquinone structures are studied in both the dilute solution state, the solid state, and as present in the PET fibers. It is proven that 1-amino anthraquinones show strong “chelate-type” intramolecular hydrogen bonding in all three states. In the fibers an important supplementary intermolecular hydrogen bonding with the CO groups in the PET fiber is observed. The extend of hydrogen bonding seems to be prone to dye concentration variations. Further analysis by modulated differential scanning calorimetry links the hydrogen bonding to an intrinsic plasticizing effect of the dyes affecting the dye diffusion process. This thus offers a tool for the fundamental understanding of the dyeing process and possible observed differences in dyeing behavior in dye–fiber systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Hypervitaminosis A-related liver toxicity may be severe and may even lead to cirrhosis. In the normal liver, vitamin A is stored in hepatic stellate cells (HSC), which are prone to becoming activated and acquiring a myofibroblast-like phenotype, producing large amounts of extracellular matrix. AIMS: In order to assess the relationship between vitamin A intake, HSC activation and fibrosis, we studied nine liver biopsies from patients belonging to a well-characterized series of 41 patients with vitamin A hepatotoxicity. METHODS: Fibrosis was underlined by Sirius-red staining, whereas activated HSC were immunohistochemically identified using an antibody against alpha smooth muscle actin. The volume density (Vv) of sinusoidal and total fibrosis and of sinusoidal and total activated HSC was quantified by the point-counting method. RESULTS: Morphology ranged from HSC hypertrophy and hyperplasia as the sole features to severe architectural distortion. There was a significant positive correlation between Vv of perisinusoidal fibrosis and the daily consumption of vitamin A (P=0.004). CONCLUSION: The close correlation between the severity of perisinusoidal fibrosis and the daily dose of the retinol intake suggests the existence of a dose-effect relationship.

Oreina cacaliae (Schrank) (Coleoptera: Chrysomelidae) has a 2-year life cycle that it has to complete within the short warm seasons of the harsh alpine environment. Three years of field observations and experiments revealed that not all beetles overwintered in the soil next to their principal host Adenostyles alliariae (Asteraceae), as was previously assumed, but that many O. cacaliae left their host in autumn and flew to overwintering sites that were extensively sun-exposed. In spring, these individuals became active 2 months earlier than their conspecifics that had remained in the soil close to the host plant. These early beetles flew from their hibernation sites against the direction of the prevailing wind. After a random landing in snow, they walked to the spring host Petasites paradoxus (Asteraceae) and fed on its floral stalks, the only plant parts present at that time. A few weeks later, they took flight again to locate newly emerging A. alliariae on which they would feed and deposit larvae as did individuals that had overwintered close to A. alliariae. Leaves of A. alliariae contain pyrrolizidine alkaloids (PAs), which the beetles sequester for their own defence. The dominating PA (seneciphylline) was also found to be present in the floral stalks of P. paradoxus. With additional behavioural assays in the field and laboratory, we demonstrated the importance of plant odours in the short-range host location process. This study reveals a unique hibernation behaviour in which part of the beetle population uses exceptionally warm locations from which they emerge in spring, long before all the snow has melted. This early, but risky emergence allows them to exploit a second, highly suitable host plant, which they locate first by wind-guided flight and then by odour-guided walking. The well-fed beetles then use odour again to move to their principal host plant, on which they reproduce.

The degree of adaptation of herbivorous insects to their local flora is an important component of the evolutionary processes that lead to host plant specialization in insects. In this study we investigated geographic variations in the oviposition preference of the leaf beetle Oreina elongata Suffrian (Coleoptera: Chrysomelidae: Chrysolini) in relation to differences in host plant specialization, in the field. We focused on the mechanisms of host choice and asked whether potential differences among populations are due to variations in host plant ranking and/or host plant specificity. We performed a combination of simultaneous choice and sequential no-choice experiments with two of the major host plants of the beetle [Cirsium spinosissimum (L.) and Adenostyles alliariae (Gouan) (Asteraceae)]. The results suggested that spatial variation in host plant specialization has resulted in differences between populations in some aspects of the oviposition choice of O. elongata, while other aspects seem unaffected. We found no variation in host plant ranking among populations, as estimated in simultaneous choice tests. In contrast, the sequential no-choice test indicated that host plant specificity was lower in a population that never encountered the highest ranked plant in the field. This finding agreed with our expectations, and we discuss our results in relation to the commonly used hierarchical threshold model. The results suggested that the mechanism for the differences in specificity is the variation among populations in the general motivation to oviposit, rather than quantitative differences in relative preference for the two hosts. We stress that it is essential to establish which of the two mechanisms is most important, as it will affect the probability of evolutionary change in host plant ranking.