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Meat consumption is declining in developed countries but increasing in emerging countries. This study, for the first time, compares the socio-behavioural factors influencing individuals' meat consumption level and meat reduction intention between Vietnam, an emerging economy and Switzerland, a developed country. Online consumer surveys were conducted in late 2022, yielding 552 usable replies from Switzerland and 592 from Vietnam for this study. Drawing upon an extended Protection Motivation Theory and using structural equation modelling, we found similarities as well as differences in the determinants of meat consumption behaviour. Perceived health risks of meat overconsumption, self-efficacy of meat reduction, attitude toward ethical and environmental issues, and pressure from family members' reluctance to change diet drove the intention to reduce meat in both countries. Meat attachment emerges as the most important determinant of meat consumption level in not only Switzerland but also Vietnam and thus presents the largest barrier to meat reduction. The association between response cost of eating less meat and intention to reduce meat was negative in Switzerland but positive in Vietnam. Self-efficacy of meat consumption reduction influenced meat consumption level solely in Switzerland. Ethical and environmental attitudes significantly facilitated meat reduction intention of Swiss respondents only, reflecting cultural differences. Policy implications were discussed.
Sujet(s)
Comportement du consommateur , Intention , Viande , Humains , Vietnam , Suisse , Mâle , Adulte , Femelle , Adulte d'âge moyen , Enquêtes et questionnaires , Jeune adulte , Régime alimentaire , Adolescent , Sujet âgé , Facteurs socioéconomiques , Comportement alimentaire , AnimauxRÉSUMÉ
Traditional approaches to coastal defence often struggle to reduce the risks of accelerated climate change. Incorporating nature-based components into coastal defences may enhance adaptation to climate change with added benefits, but we need to compare their performance against conventional hard measures. We conduct a meta-analysis that compares the performances of hard, hybrid, soft and natural measures for coastal defence across different functions of risk reduction, climate change mitigation, and cost-effectiveness. Hybrid and soft measures offer higher risk reduction and climate change mitigation benefits than unvegetated natural systems, while performing on par with natural measures. Soft and hybrid measures are more cost-effective than hard measures, while hybrid measures provide the highest hazard reduction among all measures. All coastal defence measures have a positive economic return over a 20-year period. Mindful of risk context, our results provide strong an evidence-base for integrating and upscaling nature-based components into coastal defences in lower risk areas.
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The rice root system consists of two types of lateral roots, indeterminate larger L-types capable of further branching, and determinate, short, unbranched S-types. L-type laterals correspond to the typical lateral roots of cereals whereas S-type laterals are unique to rice. Both types contribute to nutrient and water uptake and genotypic variation for density and length of these laterals could be exploited in rice improvement to enhance adaptations to nutrient and water-limited environments. Our objectives were to determine how best to screen for lateral root density and length and to identify markers linked to genotypic variation for these traits. Using different growing media showed that screening in nutrient solution exposed genotypic variation for S-type and L-type density, but only the lateral roots of soil-grown plants varied for their lengths. A QTL mapping population developed from parents contrasting for lateral root traits was grown in a low-P field, roots were sampled, scanned and density and length of lateral roots measured. One QTL each was detected for L-type density (LDC), S-type density on crown root (SDC), S-type density on L-type (SDL), S-type length on L-type (SLL), and crown root number (RNO). The QTL for LDC on chromosome 5 had a major effect, accounting for 46% of the phenotypic variation. This strong positive effect was confirmed in additional field experiments, showing that lines with the donor parent allele at qLDC5 had 50% higher LDC. Investigating the contribution of lateral root traits to P uptake using stepwise regressions indicated LDC and RNO were most influential, followed by SDL. Simulating effects of root trait differences conferred by the main QTL in a P uptake model confirmed that qLDC5 was most effective in improving P uptake followed by qRNO9 for RNO and qSDL9 for S-type lateral density on L-type laterals. Pyramiding qLDC5 with qRNO9 and qSDL9 would be possible given that trade-offs between traits were not detected. Phenotypic selection for the RNO trait during variety development would be feasible, however, the costs of doing so reliably for lateral root density traits is prohibitive and markers identified here therefore provide the first opportunity to incorporate such traits into a breeding program.
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Population's biological parameters, including length at first capture, mortalities, exploitation rates, growth coefficient, longevity, and recruitment times, are essential in assessing fishing status, but there is no data on Mystus mysticetus. Therefore, the study was conducted to provide these parameters to assess the fishing status of this species at Cai Rang, Can Tho (CRCT) and Long Phu, Soc Trang (LPST). A collection of 741 individual fish was used for analysis and showed that most fish size groups ranged from 9.0 cm to 12.0 cm, and the asymptotic length was 16.8 cm for both CRCT and LPST populations. The fish population von Bertalanffy curve was L t = 16.80(1 - e-0.51(t + 0.38)) at CRCT and L t = 16.80(1 - e-0.48(t + 0.40)) at LPST. The fish growth coefficient at CRCT (2.16) was higher than at LPST (2.13), whereas the reverse case was true for longevity ranging from 5.88 years (at CRCT) to 6.25 years (at LPST). At CRCT, fishing mortality, natural mortality, total mortality, and exploitation rate were 0.69/year, 1.40/year, 2.09/year, and 0.33, respectively; at LPST, these values were 0.75/year, 1.33/year, 2.08/year, and 0.36, respectively. Although the population parameter of this fish species exhibited a spatial variation, both CRCT and LPST fish resources have not been subjected to overexploit because E (0.33 at CRCT and 0.36 at LPST) is lower than E 0.1 (0.707 at CRCT and 0.616 at LPST).
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A micellar hydrogel has long been considered an intelligent hydrophobic drug delivery material. In this study, synthesized PLA1750-PEG1750-PLA1750 micellar hydrogel aims to encapsulate ibuprofen (IBU) in the core PLA hydrophobic of the micelle and prolong the drug release time by an injectable route. The structure and morphology of the PLA1750-PEG1750-PLA1750 copolymer hydrogel were demonstrated by 1H NMR and TEM data. The hydrogel also achieved a gel state at a high concentration of 25 wt.% under the physiological conditions of the body (37°C, pH 7.4). Besides, the biocompatibility test displayed that the hydrogel slightly affected mice after injection one week and fully recovered after four weeks. Furthermore, the in vitro degradation of the hydrogel showed apparent gel erosion after the first three weeks, which is related to the IBU release rate: slow for the first three weeks and then fast. As a result, the total drug release after three and four weeks was 18 wt.% and 41 wt.%, respectively. However, in the first 24 hours, the amount of the drug released was 10 wt.%, suggesting that the IBU drug diffused from the surface hydrogel to the buffer solution. These show that PLA1750-PEG1750-PLA1750 hydrogel can be a potential IBU drug delivery candidate.
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The use of gnobiotic brine shrimp (Artemia spp.) for ecotoxicology and bacteria-host interaction studies is common. However, requirements for axenic culture and matrix effects of seawater media can be an obstacle. Thus, we investigated the hatching ability of Artemia cysts on a novel sterile Tryptic Soy Agar (TSA) medium. Herein, we demonstrate for the first time that Artemia cysts can hatch on a solid medium without liquid, which offers practical advantages. We further optimized the culture conditions for temperature and salinity and assessed this culture system for toxicity screening of silver nanoparticles (AgNPs) across multiple biological endpoints. Results revealed that maxima hatching (90%) of embryos occurred at 28 °C and without addition of sodium chloride. When capsulated cysts were cultured on TSA solid medium Artemia were negatively impacted by AgNPs at 30-50 mgL-1 in terms of the embryo hatching ratio (47-51%), umbrella- to nauplii-stage transformation ratio (54-57%), and a reduction in nauplii-stage growth (60-85% of normal body length). At 50-100 mgL-1 AgNPs and higher, evidence of damage to lysosomal storage was recorded. At 500 mgL-1 AgNPs, development of the eye was inhibited and locomotory behavior impeded. Our study reveals that this new hatching method has applications in ecotoxicology studies and provides an efficient means to control axenic requirements to produce gnotobiotic brine shrimp.
Sujet(s)
Nanoparticules métalliques , Animaux , Nanoparticules métalliques/toxicité , Argent/toxicité , Artemia , Agar-agar/pharmacologie , Écotoxicologie , Milieux de culture/pharmacologieRÉSUMÉ
Corneal haze brought on by fibrosis due to insult can lead to partial or complete vision loss. Currently, corneal transplantation is the gold standard for treating severe corneal fibrosis, which comes with the risk of rejection and the issue of donor tissue shortages. Sphingolipids (SPLs) are known to be associated with fibrosis in various tissues and organs, including the cornea. We previously reported that SPLs are tightly related to Transforming Growth Factor ß (TGF-ß) signaling and corneal fibrogenesis. This study aimed to elucidate the interplay of SPLs, specifically sphingosine-1-phosphate (S1P) signaling, and its' interactions with TGF-ß signaling through detailed analyses of the corresponding downstream signaling targets in the context of corneal fibrosis, in vitro. Healthy human corneal fibroblasts (HCFs) were isolated, plated on polycarbonate membranes, and stimulated with a stable Vitamin C derivative. The 3D constructs were treated with either 5 µM sphingosine-1-phosphate (S1P), 5 µM SPHK I2 (I2; inhibitor of sphingosine kinase 1, one of the two enzymes responsible for generating S1P in mammalian cells), 0.1 ng/mL TGF-ß1, or 0.1 ng/mL TGF-ß3. Cultures with control medium-only served as controls. All 3D constructs were examined for protein expression of fibrotic markers, SPLs, TGF-ßs, and relevant downstream signaling pathways. This data revealed no significant changes in any LTBP (latent TGF-ß binding proteins) expression when stimulated with S1P or I2. However, LTBP1 was significantly upregulated via stimulation of TGF-ß1 and TGF-ß3, whereas LTBP2 was significantly upregulated only with TGF-ß3 stimulation. Significant downregulation of TGF-ß receptor II (TGF-ßRII) following S1P stimulation but significant upregulation following I2 stimulation was observed. Following TGF-ß1, S1P, and I2 stimulation, phospho-SMAD2 (pSMAD2) was significantly downregulated. Furthermore, I2 stimulation led to significant downregulation of SMAD4. Adhesion/proliferation/transcription regulation targets, SRC, FAK, and pERK 1/2 were all significantly downregulated by exogenous S1P, whereas I2 only significantly downregulated FAK. Exogenous TGF-ß3 caused significant upregulation of AKT. Interestingly, both I2 and TGF-ß3 caused significant downregulation of JNK expression. Lastly, TGF-ß1 led to significant upregulation of sphingosine kinase 1 (SphK1) and sphingosine-1-phosphate receptor 3 (S1PR3), whereas TGF-ß3 caused significant upregulation of only SphK1. Together with previously published work from our group and others, S1P inhibition exhibits great potential as an efficacious anti-fibrotic modality in human corneal stromal ECM. The current findings shed further light on a very complex and rather incompletely investigated mechanism, and cement the intricate crosstalk between SPLs and TGF-ß in corneal fibrogenesis. Future studies will dictate the potential of utilizing SPLs/TGF-ß signaling modulators as novel therapeutics in corneal fibrosis.
Sujet(s)
Sphingolipides , Facteur de croissance transformant bêta , Animaux , Humains , Sphingolipides/métabolisme , Facteur de croissance transformant bêta/pharmacologie , Facteur de croissance transformant bêta/métabolisme , Facteur de croissance transformant bêta-1/métabolisme , Stroma de la cornée/métabolisme , Facteur de croissance transformant bêta-3 , Transduction du signal , Lysophospholipides/pharmacologie , Lysophospholipides/métabolisme , Sphingosine/pharmacologie , Sphingosine/métabolisme , Fibrose , Mammifères , Protéines de liaison au TGF-bêta latentRÉSUMÉ
BACKGROUND: Severe Hurley stage 1 hidradenitis suppurativa (HS1) is a difficult-to-treat form of the disease. OBJECTIVE: To assess the efficacy and tolerance of the oral combination of rifampin (10 mg/kg once daily)/moxifloxacin (400 mg once daily)/metronidazole (250-500 mg 3 times daily) (RMoM) treatment strategy in patients with severe HS1. METHODS: Prospective, open-label, noncomparative cohort study in 28 consecutive patients. Nineteen patients were treated for 6 weeks by RMoM, followed by 4 weeks of rifampin/moxifloxacin alone, then by cotrimoxazole after remission. Moxifloxacin was replaced by pristinamycin (1 g 3 times daily) in 9 patients because of contraindications or intolerance. The primary endpoint was a Sartorius score of 0 (clinical remission) at week 12. RESULTS: The median Sartorius score dropped from 14 to 0 (P = 6 × 10-6) at week 12, with 75% of patients reaching clinical remission. A low initial Sartorius score was a prognosis factor for clinical remission (P = .049). The main adverse effects were mild gastrointestinal discomfort, mucosal candidiasis, and asthenia. At 1 year of follow-up, the median number of flares dropped from 21/year to 1 (P = 1 × 10-5). LIMITATIONS: Small, monocentric, noncontrolled study. CONCLUSIONS: Complete and prolonged remission can be obtained in severe HS1 by using targeted antimicrobial treatments.
Sujet(s)
Hidrosadénite suppurée , Humains , Hidrosadénite suppurée/traitement médicamenteux , Rifampicine/effets indésirables , Moxifloxacine/usage thérapeutique , Métronidazole/effets indésirables , Études prospectives , Études de suivi , Études de cohortes , Indice de gravité de la maladie , Résultat thérapeutiqueRÉSUMÉ
The Squaretail mullet Ellochelon vaigiensis is widely found from marine to brackish and freshwater, including the Vietnamese Mekong Delta (VMD). Data on the length-weight relationships (LWRs), growth pattern, and condition factor (CF) play an essential role in fisheries assessment but are limited to E. vaigiensis - a commercial fish in VMD. To better understand the growth pattern of this fish, the study collected samples at four sites, including Thanh Phu, Ben Tre (BT); Duyen Hai, Tra Vinh (TV); Tran De, Soc Trang (ST); and Dong Hai, Bac Lieu (BL). Each month, fish samples were collected using bottom nets at each sampling site during high tide in both the dry season (January to May 2021) and the wet season (November to December 2020 and June to October 2021). This study qualified whether LWRs, growth pattern, and CF of E. vaigiensis vary with sexual, intraspecific, and spatiotemporal variables. The analysis results of 942 specimens showed that fish total length (TL = 17.86 ± 0.13 cm) and weight (W = 54.29 ± 1.05 g) changed with sex, season, month and site. The W could be appraised from a given TL due to high coefficients (r 2 ) of LWRs that were regulated by fish size and season but not sex. The species showed negative allometry as its slope value of LWRs (b = 2.34 ± 0.30) was <3. The growth pattern did not change with sex and site but varied fish size, season, and months ranging from negative allometry to isometry. The CF of females (1.08 ± 0.01) was higher than males (0.99 ± 0.01). Albeit this fish showed spatiotemporal variation in CF, ranging from 0.81 ± 0.01 to 1.25 ± 0.02, the CF (1.02 ± 0.01) was significantly higher than the one threshold, indicating that E. vaigiensis lived a favorable condition. Research results show that this fish species has a dominant growth pattern in terms of length (b < 3) and is well adapted to the environment (CF ≈ 1). These data have an important role in suggesting the future aquaculture of this fish.
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Recent studies have shown that using international guidelines to diagnose metabolic syndrome (MetS) may underestimate its prevalence in different Asian populations. This study aims to determine the validity of anthropometric indicators and appropriate cut-off values to predict MetS for Vietnamese adults. We analyzed data on 4701 adults across four regions of Vietnam. Four conventional and five novel anthropometric indexes were calculated. The area under a receiver operating characteristic (ROC) curve (AUC) and Youden's J statistic were applied to evaluate the diagnostic ability and optimal cut-off values. Regardless of diagnostic criteria and gender, Abdominal volume index (AVI), Body roundness index (BRI), and Waist-height ratio (WHtR) had the highest AUC values, followed by Body mass index (BMI) and Waist-hip ratio (WHR). However, it was seen that differences among the AUC values of most indices were minor. In men, using International Diabetes Federation (IDF) criteria, the threshold of indices was 3.86 for BRI, 16.20 for AVI, 0.53 for WHtR, 22.40 for BMI, and 0.90 for WHR. In women, the threshold for these figures were 3.60, 12.80, 0.51, 23.58, and 0.85, respectively. It is recommended that health personnel in Vietnam should apply appropriate thresholds of anthropometry, which are lower than current international guidelines, for MetS screening to avoid under-diagnosis.
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Syndrome métabolique X , Adulte , Anthropométrie , Indice de masse corporelle , Femelle , Humains , Mâle , Syndrome métabolique X/diagnostic , Syndrome métabolique X/épidémiologie , Courbe ROC , Facteurs de risque , Vietnam/épidémiologie , Tour de taille , Rapport tour de taille sur taille , Rapport taille-hanchesRÉSUMÉ
Nature contributes substantially to human well-being through its diverse material and nonmaterial contributions. However, despite the growing literature on the nonmaterial dimensions of human-nature relations, we lack a systematic understanding of how they are linked with human well-being. Here, we use the concept of cultural ecosystem services (CESs) as a lens to explore this interface. Through a systematic review of the peer-reviewed literature, we elicit the unique pathways and mechanisms linking individual CESs and constituents of human well-being, as well as their relative effects. Subsequently, we identify their complex interactions through latent class analysis and multiple correspondence analysis, which delineate five major assemblages that reflect synergies and trade-offs at the interface of CESs and human well-being. We critically discuss key research trends and gaps and propose directions for future research and practice to leverage the potential of the nonmaterial contributions of nature for human well-being and sustainability more broadly.
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[This corrects the article DOI: 10.1039/D2RA01759H.].
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In the present work, nanothermometers based on amorphous zirconium metal-organic frameworks co-doped with rare-earth ions (YZ-BDC:Eu3+,Tb3+ nanothermometers) with sizes of about 10-30 nm were successfully synthesized via a microwave-assisted hydrothermal method at 120 °C for 15 min. The determined BET surfaces area, total pore volume and average pore diameter were â¼530 m2 g-1, 0.45 cm3 g-1 and 3.4 nm, respectively. Based on Fourier transform infrared spectroscopy (FTIR) and simultaneous thermal analysis (STA) results, the formation process of carboxylic acid salts and the molecular formula of the samples have been proposed. The thermometric properties of Zr-BDC:Eu3+,Tb3+ nanothermometers and their Y3+ ion co-doped counterparts (YZ-BDC:Eu3+,Tb3+) measured in the 133-573 K temperature range were compared. Moreover, the temperature-dependent CIE(x, y) chromaticity coordinates and emission color of the samples were also determined. As the temperature increased from 133 to 573 K, the emission color of Zr-BDC:Eu3+,Tb3+ nanothermometers without the presence of Y3+ ions changed from orange to red, while for YZ-BDC:Eu3+,Tb3+ nanothermometers, the emission color changed from yellow to orange, due to the strong effect of the presence of Y3+ ions on the luminescence intensity of Eu3+ and Tb3+ ions. The maximum relative sensitivity (S Rmax) in both materials was close to 0.5%/K, however, the temperature range of their occurrence was significantly shifted toward higher temperatures due to doping with Y3+ ions. The obtained results showed that doping with Y3+ ions not only enables the modulation of the useful temperature range with high relative sensitivity, but also provides improved thermal stability.
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Diabetic keratopathy is a corneal complication of diabetes mellitus (DM). Patients with diabetic keratopathy are prone to developing corneal haze, scarring, recurrent erosions, and significant wound healing defects/delays. The purpose of this study was to determine the contractility profiles in the diabetic human corneal stromal cells and characterize their molecular signatures. Primary human corneal fibroblasts from healthy, Type 1 DM (T1DM), and Type 2 DM (T2DM) donors were cultured using an established 3D collagen gel model. We tracked, measured, and quantified the contractile footprint over 9 days and quantified the modulation of specific corneal/diabetes markers in the conditional media and cell lysates using western blot analysis. Human corneal fibroblasts (HCFs) exhibited delayed and decreased contractility compared to that from T1DMs and T2DMs. Compared to HCFs, T2DMs demonstrated an initial downregulation of collagen I (day 3), followed by a significant upregulation by day 9. Collagen V was significantly upregulated in both T1DMs and T2DMs based on basal secretion, when compared to HCFs. Cell lysates were upregulated in the myofibroblast-associated marker, α-smooth muscle actin, in T2DMs on day 9, corresponding to the significant increase in contractility rate observed at the same time point. Furthermore, our data demonstrated a significant upregulation in IGF-1 expression in T2DMs, when compared to HCFs and T1DMs, at day 9. T1DMs demonstrated significant downregulation of IGF-1 expression, when compared to HCFs. Overall, both T1DMs and T2DMs exhibited increased contractility associated with fibrotic phenotypes. These findings, and future studies, may contribute to better understanding of the pathobiology of diabetic keratopathy and ultimately the development of new therapeutic approaches.
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Forme de la cellule/physiologie , Maladies de la cornée/anatomopathologie , Stroma de la cornée/cytologie , Fibroblastes/cytologie , Cellules stromales/cytologie , Techniques de cultures cellulaires tridimensionnelles/méthodes , Cellules cultivées , Collagène de type I/métabolisme , Collagène de type III/métabolisme , Collagène de type V/métabolisme , Maladies de la cornée/étiologie , Maladies de la cornée/métabolisme , Stroma de la cornée/métabolisme , Diabète de type 1/complications , Diabète de type 2/complications , Fibroblastes/métabolisme , Humains , Facteur de croissance IGF-I/métabolisme , Adulte d'âge moyen , Récepteur IGF de type 1/métabolisme , Cellules stromales/métabolisme , Facteurs tempsRÉSUMÉ
STEM education has been considered foundational to economic growth by many countries. It has received great attention from various educational systems, but the actual implementation has triggered several problems, especially in developing countries in Asia. This qualitative study investigated the challenges to STEM education in public high schools in Vietnam. The participants were ten experienced teachers from ten different schools in a Vietnamese central province. The data were collected from in-depth semi-structured interviews. Analysis of the transcripts of the interview recordings showed that the teachers faced many challenges regarding their interdisciplinary knowledge and teaching methods, curriculum, practical constraints, and beliefs about effective STEM education. Notably, the findings concerning the teachers' beliefs about effective STEM education and the tension between their beliefs and the teaching goals were closely related to the local cultural values and the expectations of the schooling system. The findings of the study were discussed in relation to the local contextual factors and cultural values. Implications for teacher pedagogy and professional development regarding STEM education for Vietnamese high school contexts, and beyond, are discussed.
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Herein, Fe-doped C3N4 high-performance photocatalysts, synthesized by a facile and cost effective heat stirring method, were investigated systematically using powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) surface area measurement, X-ray photoelectron (XPS), UV-Vis diffusion reflectance (DRS) and photoluminescence (PL) spectroscopy. The results showed that Fe ions incorporated into a g-C3N4 nanosheet in both +3 and +2 oxidation states and in interstitial configuration. Absorption edge shifted slightly toward the red light along with an increase of absorbance in the wavelength range of 430-570 nm. Specific surface area increased with the incorporation of Fe into g-C3N4 lattice, reaching the highest value at the sample doped with 7 mol% Fe (FeCN7). A sharp decrease in PL intensity with increasing Fe content is an indirect evidence showing that electron-hole pair recombination rate decreased. Interestingly, Fe-doped g-C3N4 nanosheets present a superior photocatalytic activity compared to pure g-C3N4 in decomposing RhB solution. FeCN7 sample exhibits the highest photocatalytic efficiency, decomposing almost completely RhB 10 ppm solution after 30 min of xenon lamp illumination with a reaction rate approximately ten times greater than that of pure g-C3N4 nanosheet. This is in an agreement with the BET measurement and photoluminescence result which shows that FeCN7 possesses the largest specific surface area and low electron-hole recombination rate. The mechanism of photocatalytic enhancement is mainly explained through the charge transfer processes related to Fe2+/Fe3+ impurity in g-C3N4 crystal lattice.
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This paper presents the use of soft template method to synthesize core and core-shell up-converting nanoparticles usefull for temperature sensing applications. Based on the stock solutions of core ß-NaYF4:Er3+,Yb3+ nanoparticles and involving soft template method without any additional process of surface functionalization, it is possible to directly design the core-shell ß-NaYF4:Er3+,Yb3+@NaYF4 nanoparticles, which can be perfectly dispersed in cyclohexane and surfactants like oleic acid (OA), triethanolamine (TEA) or Cetyltrimethylammonium bromide (CTAB). The morphological, crystalline and elemental characteristics of samples were investigated by Field Emission Scanning Electron Microscopy, X-Ray Diffraction, High Resolution Transmission Electron Microscopy, Selected Area Electron Diffraction patterns and Energy-Dispersive X-Ray Spectroscopy (EDX) measurements. The results showed that the synthesized NaYF4:Er3+,Yb3+@NaYF4 core-shell nanoparticles have roughly spherical shape, pure hexagonal ß phase with core size of about 35 ± 5 nm and shell thickness of about 40 ± 5 nm. It has been shown that the coating of the ß-NaYF4:Er3+,Yb3+ core with NaYF4 shell layer enables to enhance the green upconversion (UC) emission intensities in respect to red one. Under 976 nm excitation, the synthesized ß-NaYF4:2%Er3+,19%Yb3+@NaYF4 core-shell nanoparticles revealed three strong emission bands at 520 nm, 545 nm and 650 nm corresponding to 2H11/2, 4S3/2 and 4F9/2 to 4I15/2 transitions of Er3+ ions with the lifetimes of 215, 193 and 474 µs, respectively. The calculated CIE chromaticity coordinates proved that the emission colour of core-shell nanoparticles was changed from red into yellowish green upon increasing the power density of the 976 nm laser from 0.73 to 9.95 W/cm2. The calculated slopes indicated that in the ß-NaYF4:2%Er3+,19%Yb3+@NaYF4 core-shell nanoparticles, two-photon and three-photon UC processes took place simultaneously. Although the former one is similar as in the case of ß-NaYF4:Er3+,Yb3+ bare core nanoparticles, the latter one, three-photon UC process for green emission occurs, due to cross relaxation processes of two Er3+ ions only within nanoparticles with core-shell architecture. Moreover, the energy difference between the 2H11/2 and 4S3/2 levels and associated constant of NaYF4@NaYF4 host lattice were determined and they reached ~ 813 cm-1 and 14.27 (r2 = 0.998), respectively. In order to investigate the suitability of nanoparticles for optical temperature sensing, the emission spectra were measured in a wide temperature range from 158 to 298 K. An exceptionally high value of relative sensitivity was obtained at 158 K and it amounted to 4.25% K-1. Further temperature increase resulted in gradual decrease of relative sensitivity, however, it maintained a high value > 1% K-1 in the entire analyzed temperature range.
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Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the skin associated with specific lesional dysbiotic features. We studied the microbiome of clinically unaffected typical HS sites (armpits, inguinal folds, and gluteal clefts) in 60 patients with HS and 17 healthy controls. A total of 192 samples obtained by swabbing were analyzed by bacterial cultures. Of these, 116 randomly selected samples were studied by 16S rRNA gene amplicon sequencing. Patients and controls showed similar characteristics, except for smoking (87% vs. 6%, respectively). HS skinfolds were characterized by an increased abundance of anaerobes, predominantly Prevotella, but also Actinomyces, Campylobacter ureolyticus, and Mobiluncus, contrasting with a lower abundance of skin commensals such as Staphylococcus epidermidis, a major component of the skin microbiome; Kocuria; and Micrococcus luteus. The following three independent factors were associated with an abundance of high anaerobes by multivariate analysis: samples originating from patients with HS patients (P = 2.1 × 10-4); body mass index (P = 5 × 10-5); and the sampling site, the gluteal cleft being the most anaerobic area, followed by inguinal folds and axilla (P = 3 × 10-6). The microbiome of clinically unaffected HS skinfolds is reminiscent, albeit to a minor extent, of the microbiome of chronic suppurative HS lesions and may fuel inflammation at a preclinical stage of the disease.
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Bactéries anaérobies/immunologie , Hidrosadénite suppurée/immunologie , Microbiote/immunologie , Peau/microbiologie , Adulte , Bactéries anaérobies/génétique , Bactéries anaérobies/isolement et purification , Études transversales , ADN bactérien/génétique , ADN bactérien/isolement et purification , Femelle , Volontaires sains , Hidrosadénite suppurée/diagnostic , Hidrosadénite suppurée/microbiologie , Humains , Mâle , Microbiote/génétique , Adulte d'âge moyen , Études prospectives , ARN ribosomique 16S/génétique , Analyse de séquence d'ADN , Indice de gravité de la maladie , Peau/immunologie , Jeune adulteSujet(s)
Amyloid precursor protein secretases/génétique , Hidrosadénite suppurée/génétique , Mutation , Adolescent , Adulte , Sujet âgé , Amyloid precursor protein secretases/physiologie , Études de cohortes , Femelle , Humains , Mâle , Glycoprotéines membranaires/génétique , Protéines membranaires/génétique , Adulte d'âge moyen , Préséniline-1/génétique , Jeune adulteRÉSUMÉ
Photonic crystals (PhC) are spatially ordered structures with lattice parameters comparable to the wavelength of propagating light. Their geometrical and refractive index features lead to an energy band structure for photons, which may allow or forbid the propagation of electromagnetic waves in a limited frequency range. These unique properties have attracted much attention for both theoretical and applied research. Devices such as high-reflection omnidirectional mirrors, low-loss waveguides, and high- and low-reflection coatings have been demonstrated, and several application areas have been explored, from optical communications and color displays to energy harvest and sensors. In this latter area, photonic crystal fibers (PCF) have proven to be very suitable for the development of highly performing sensors, but one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) PhCs have been successfully employed, too. The working principle of most PhC sensors is based on the fact that any physical phenomenon which affects the periodicity and the refractive index of the PhC structure induces changes in the intensity and spectral characteristics of the reflected, transmitted or diffracted light; thus, optical measurements allow one to sense, for instance, temperature, pressure, strain, chemical parameters, like pH and ionic strength, and the presence of chemical or biological elements. In the present article, after a brief general introduction, we present a review of the state of the art of PhC sensors, with particular reference to our own results in the field of mechanochromic sensors. We believe that PhC sensors based on changes of structural color and mechanochromic effect are able to provide a promising, technologically simple, low-cost platform for further developing devices and functionalities.