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1.
MethodsX ; 12: 102666, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38559386

RESUMO

Domestic-oriented research focusing on food requires methodologies that closely mimic practices occurring in home kitchens while meeting scientific standards. Currently however, there is a lack of methodologies that can be implemented in both laboratory and home environments. This paper proposes a method that fulfills the scientific requirements of repeatability and reproducibility, while utilizing commonly available materials and processes found in the average household. The method is applied to the preparation, boiling, and seasoning of roots of Daucus carota L. ("carrots"), which can be employed in various scientific fields with only minor adjustments. Three scientific experiments utilizing this methodology are presented, namely sensory evaluation, ionic chromatography measurements, and NMR experiments. In the existing literature, numerous protocols have been used for carrot sample preparation, hindering direct comparisons between studies. In this paper we would like to highlight the ability of the methodology to enhance comparability, as well as its potential utilization in other research applications. The main principles underlying the proposed methodology can also be extrapolated to prepare samples of several other vegetables or cereals.•Comprehensive guidelines for standardizing the shapes, lengths, and widths of carrots are outlined, ensuring minimal variability while preserving the integrity of the raw material.•The cooking method for carrots is tailored to utilize commonly available household materials, while meeting scientific standards required for research purposes.•Seasoning practices involving readily available domestic materials, like commercial salt, are suggested.

2.
Herit Sci ; 12(1): 26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38283177

RESUMO

The bronze doors of the Basilica of San Zeno in Verona, Italy, are a special case in art history research. They were made by several workshops during the twelfth century: stylistically, two to three workshops were assumed to produce the metal parts of the door. However, it is still unclear when exactly and if this interpretation can be supported by the chemical composition of the metal. In this research we aimed to verify the art history interpretation by identifying the alloy composition of each individual metal plate. The composition of the supporting wooden structures are discussed. A portable ED-XRF instrument and optical microscopes were used to analyse and document the doors non-invasively. The doors were also photographed to produce high resolution orthophotos and 3D models. We can confirm that the metal parts of the doors were made of leaded tin-bronze as well as leaded brass and mounted on a wooden structure mainly made of spruce and oak wood. Chemically, two/three different groups of alloys have been identified, which can be associated with two or three different workshops, and which largely correspond to the stylistic interpretation. Supplementary Information: The online version contains supplementary material available at 10.1186/s40494-024-01143-2.

3.
Polymers (Basel) ; 15(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38006155

RESUMO

Lignins released in the black liquors of kraft pulp mills are an underutilised source of aromatics. Due to their phenol oxidase activity, laccases from ligninolytic fungi are suitable biocatalysts to depolymerise kraft lignins, which are characterised by their elevated phenolic content. However, the alkaline conditions necessary to solubilise kraft lignins make it difficult to use fungal laccases whose activity is inherently acidic. We recently developed through enzyme-directed evolution high-redox potential laccases active and stable at pH 10. Here, the ability of these tailor-made alkaliphilic fungal laccases to oxidise, demethylate, and depolymerise eucalyptus kraft lignin at pH 10 is evidenced by the increment in the content of phenolic hydroxyl and carbonyl groups, the methanol released, and the appearance of lower molecular weight moieties after laccase treatment. Nonetheless, in a second assay carried out with higher enzyme and lignin concentrations, these changes were accompanied by a strong increase in the molecular weight and content of ß-O-4 and ß-5 linkages of the main lignin fraction, indicating that repolymerisation of the oxidised products prevails in one-pot reactions. To prevent it, we finally conducted the enzymatic reaction in a bench-scale reactor coupled to a membrane separation system and were able to prove the depolymerisation of kraft lignin by high-redox alkaliphilic laccase.

4.
Front Nutr ; 10: 1200049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024369

RESUMO

The correct identification of malnourished patients in the context of hip, knee, or spine surgery research would enhance the quality of analytical studies investigating the prediction potential of preoperative nutritional disorders on postoperative recovery. However, accurate malnutrition screening and diagnostic assessment rely on parameters that were not routinely collected in routine practice until a few years ago. The authors of this article present substitute literature-based equations that can be built up using historical routinely collected data to classify patients that had been at risk of malnutrition or malnourished. For what concerns the risk screening, several methods are available to identify patients at risk of over- or undernutrition, encompassing the BWd (body weight difference from the ideal weight), GNRI (geriatric nutritional risk index), INA (instant nutritional assessment), LxA (combination of lymphocyte count and albumin), PMA (protein malnutrition with acute inflammation), PMAC (protein malnutrition with acute and chronic inflammation), IDM (iron deficit malnutrition), and VBD (vitamin B deficit malnutrition). Conversely, the GLIM (global leadership initiative on malnutrition) criteria can be used to assess malnutrition and diagnose subclasses of undernutrition. Rational use of these tools can facilitate the conduction of efficient prospective studies in the future, as well as bespoke retrospective cohort studies and database research.

5.
Food Sci Nutr ; 11(10): 6648-6659, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37823106

RESUMO

The objectives of this study were to evaluate sensory, chemical, and physical characteristics of olive oil prepared by three flavoring methods and analyze changes during storage (0, 3, and 6 months). Favored olive oil was prepared by three flavoring methods (fresh, dried, and essential oil). Selected sensory, chemical, and color parameters were monitored based on international standards. The color was determined by spectrophotometer. The results confirmed that storage time and flavoring method affect sensory characteristics of the oil. Fresh garlic oil had significantly lower (p < .05) fruity smell. The level of pungent taste significantly increased (p < .05) in the dried rosemary oil, rosemary essential oil, and fresh and dried garlic flavored oils. The intensity of rosemary smell in the sample flavored with essential oil significantly decreased (p < .05) during storage. Opposite effect was observed in the sample flavored with dried rosemary, where the smell significantly increased (p < .05) during storage. The intensity of taste significantly increased (p < .05) in samples flavored by dried rosemary during storage. The peroxide value of all flavored oils samples increased (p < .05) during storage compared to unflavored oil where peroxide value did not change. Color indicators L*, a*, and b* show that addition of fresh rosemary causes the greatest change in olive oil color. The color change, especially the turbidity, was not perceived positive by tasters.

6.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446762

RESUMO

We optimized an ultrasound-assisted extraction process of Phellinus linteus mycelium polysaccharides (PLPs) and studied their monosaccharide composition and bacteriostatic properties. Based on a single-factor experiment, a three-factor, three-level Box-Behnken design was used to optimize the ultrasound-assisted extraction process of PLP, using the yield of PLP as the index. The chemical composition and monosaccharide composition of PLP were determined by chemical analysis and HPLC analysis, respectively. Microscopic morphological analysis of the surface of PLP was performed via swept-surface electron microscopy. The bacteriostatic properties of PLP were determined using the spectrophotometric turbidimetric method. The results showed that the best extraction process of PLP with ultrasonic assistance achieved a result of 1:42 g/mL. In this method, the ultrasonic temperature was 60 °C, ultrasonic extraction was performed for 20 min, and the yield of PLP was 12.98%. The monosaccharide composition of PLP mainly contains glucose (Glc), mannose (Man), galactose (Gal), and glucuronic acid (GlcA). The intracellular polysaccharide of Phellinus igniarius Mycelia (PIP) is an irregular spherical accumulation, the surface is rough and not smooth, and the extracellular polysaccharide (PEP) is a crumbly accumulation. PIP has a stronger inhibitory ability for S. aureus and E. coli and a slightly weaker inhibitory effect for B. subtilis; the inhibitory effect of PEP on S. aureus, E. coli, and B. subtilis is slightly inferior to that of PIP.


Assuntos
Escherichia coli , Staphylococcus aureus , Humanos , Polissacarídeos/farmacologia , Polissacarídeos/química , Monossacarídeos
7.
Waste Manag ; 168: 334-343, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37336141

RESUMO

During biogas production, a residual by-product rich in organic matter, nutrients, and trace elements - called digestate - is generated. Due to the nature of the anaerobic digestion process (i.e., conversion of organic matter into biogas) and the non-digestibility of trace elements, metal concentrations are higher in digestate than initially in the treated feedstock, resulting in a detrimental effect on the environment when directly applied as fertiliser on the soil. This study aims to predict the concentration of heavy metals in digestate through four different process parameters (Biogas yield - M1, Biodegradable fraction - M2, Dry matter - M3 and Power generation - M4) in full-scale biogas plants. For the validation of the process parameters, the predictions were compared against laboratory analyses of feedstocks and digestates samples from mono- and co-digestion processes. The convergence between the conversion factors based on laboratory data and process parameters (CLD and CFA, respectively) ranged in the following order: M3 > M2 > M1 > M4. Based on laboratory analyses, better predictions were obtained for Al, Cr, Cu, Fe, Mn, and Zn employing M3. Moreover, a robust convergence was achieved between the CLD and CFA conversion factors for the mono-digestion process. Further assessment of a diverse range of feedstocks is needed to increase the convergence between the conversion factors based on process parameters and laboratory data, specifically for the co-digestion process M3. The concentrations of Cd, Co, Ni, and Pb elements were below the detection limits, whereas Cr, Cu, and Zn did not exceed the legal threshold limits of the legislations.


Assuntos
Metais Pesados , Oligoelementos , Esterco , Biocombustíveis , Anaerobiose , Metais Pesados/análise
8.
Metabolites ; 13(6)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37367919

RESUMO

The ever-increasing human population, the problem associated with climate change and recent crises-COVID-19 disease and trade conflicts-all impacted on the availability and cost of animal feed raw materials. This is clearly visible in realities which heavily rely on importation such as islands and small states, where producers involved in the agricultural sector were strongly affected by the sharp increase in prices. To deal with these global issues, alternative resources are perceived to replace conventional ingredients. This work aimed at assessing the nutritive value of different resources (sheep feed, mature carob, Maltese bread, wild asparagus, prickly lettuce, and loquat) for small ruminants present in the Maltese Islands, analyzing their chemical composition, gas production kinetics and antioxidant properties. In general, the variation in chemical composition resulted in different rumen fermentation kinetics (p < 0.007). The ratio between GP-24 h and GP-48 h was higher in Maltese bread than other substrates; loquat, prickly lettuce and wild asparagus showed lower fermentation kinetics in accordance with their high NDF and ADF contents. The antioxidant activity may be partially related to the polyphenolic content that was higher in wild asparagus, prickly lettuce and loquat. All feed characteristic confirmed their potential to be included as ingredients in ruminant diets and as a source of fiber.

9.
Antioxidants (Basel) ; 12(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37237887

RESUMO

SPME-GC-MS and PTR-ToF-MS techniques were applied to describe the content of volatile flavor compounds in a craft beer before and after adding spirulina. The obtained results showed that the volatile profile of the two beer samples differed. Furthermore, to chemically characterize biomass spirulina, a derivatization reaction followed by GC-MS analysis was performed, highlighting a high content of molecules belonging to different chemical classes, such as sugars, fatty acids and carboxylic acids. A spectrophotometric analysis of total polyphenols and tannins, investigation into the scavenging activity towards DPPH and ABTS radicals and confocal microscopy of brewer's yeast cells were carried out. Moreover, the cytoprotective and antioxidant properties towards the oxidative damage induced by tert-butyl hydroperoxide (tBOOH) in human H69 cholangiocytes were investigated. Finally, the modulation of Nrf2 signaling under oxidative stress conditions was also evaluated. Both samples of beer were shown to contain similar levels of total polyphenols and tannins, with slightly increased levels in that containing spirulina 0.25% w/v. Moreover, the beers were found to be endowed with radical scavenging properties towards both DPPH and ABTS radicals, albeit with a weak contribution of spirulina; however, a higher riboflavin content was detected in spirulina-treated yeast cells. Conversely, the addition of spirulina (0.25% w/v) appeared to improve the cytoprotective properties of beer towards tBOOH-induced oxidative damage in H69 cells and reduce intracellular oxidative stress. Accordingly, the cytosolic Nrf2 expression was found to be increased.

10.
Chemosphere ; 331: 138789, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37116726

RESUMO

Assessing the impact of chemical contaminants on aquatic ecosystem health remains challenging due to complex exposure scenarios and the myriad of impact metrics to consider. To expand the breadth of compounds monitored and evaluate the potential hazard of environmental mixtures, cell-based bioassays (estrogen receptor alpha (ERα) and aryl hydrocarbon receptor (AhR)) and non-targeted chemical analyses with high resolution mass spectrometry (NTA-HRMS) were used to assess the quality of ∼70 marine sediment samples collected from 5 distinct coastal and offshore habitats of the Southern California Bight. AhR responses (<0.12-4.5 ng TCDD/g dry weight) were more frequently detectable and more variable than for ERα (<0.1-0.5 ng E2/g dry weight). The range of AhR and ERα responses increased by habitat as follows: Channel Islands < Mid-shelf < Marinas < Ports < Estuaries. The narrow range and magnitude of ERα screening response suggested limited potential for estrogenic impacts across sediments from all 5 habitats. The AhR response was positively correlated with total PAH and PCB concentrations and corresponded with a chemical score index representing the severity of metal and organic contamination. NTA-HRMS fingerprints generated in positive electrospray ionization mode were clearly distinguishable among coastal vs. offshore samples, with the greatest chemical complexity (n = 982 features detected) observed in estuarine sediment from a highly urbanized watershed (Los Angeles River). The concordance and complementary nature of bioscreening and NTA-HRMS results indicates their utility as holistic proxies for sediment quality, and when analyzed in conjunction with routine targeted chemical monitoring, show promise in identifying unexpected contaminants and novel toxicants.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , California , Ecossistema , Monitoramento Ambiental/métodos , Receptor alfa de Estrogênio , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise
11.
Contact Dermatitis ; 88(5): 389-394, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36661377

RESUMO

BACKGROUND: Nail stickers and nail tips are increasingly used nail products in Korea, and the rest of the world. However, no studies have examined if these specific consumer products might contain nickel, cobalt, and/or chromium, that is, metals known to provoke contact allergy. OBJECTIVE: We aimed to assess the release and content of nickel, cobalt, and chromium in nail stickers and tips by performing qualitative and quantitative analyses, respectively, of 50 convenience samples purchased in Korea. METHODS: Eighty-six qualitative spot tests were performed to determine the release of nickel, cobalt, and chromium on 35 nail stickers and 15 nail tips across five brands. Subsequently, the metal contents were quantified using inductively coupled plasma-optical mass spectrometry (ICP-MS). RESULTS: According to the spot tests, nickel was released in 7/86 (8.1%) tests before and 10/86 (11.6%) tests after exposure to artificial sweat. Cobalt and chromium (VI) spot test results were negative. However, ICP-MS detected nickel, cobalt, and chromium in 11%, 6.3%, and 16.7% of the samples, respectively. Detection rates were higher in nail tips than in stickers and were most common in rhinestones. CONCLUSION: Nail stickers and tips may contain nickel, cobalt, and/or chromium.


Assuntos
Dermatite Alérgica de Contato , Níquel , Humanos , Níquel/efeitos adversos , Níquel/análise , Cobalto/análise , Cromo/análise , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/diagnóstico , República da Coreia
12.
Int J Mol Sci ; 23(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36555489

RESUMO

The work focused on the analysis of two cultivars of tomato (Solanum lycopersicum L.), Aragon and Gladis, under two different treatments of silicon, Low, 2 L of 0.1 mM CaSiO3, and High, 0.5 mM CaSiO3, weekly, for 8 weeks, under stress-free conditions. We subsequently analyzed the morphology, chemical composition, and elemental distribution using synchrotron-based µ-XRF techniques, physiological, and molecular aspects of the response of the two cultivars. The scope of the study was to highlight any significant response of the plants to the Si treatments, in comparison with any response to Si of plants under stress. The results demonstrated that the response was mainly cultivar-dependent, also at the level of mitochondrial-dependent oxidative stress, and that it did not differ from the two conditions of treatments. With Si deposited mainly in the cell walls of the cells of fruits, leaves, and roots, the treatments did not elicit many significant changes from the point of view of the total elemental content, the physiological parameters that measured the oxidative stress, and the transcriptomic analyses focalized on genes related to the response to Si. We observed a priming effect of the treatment on the most responsive cultivar, Aragon, in respect to future stress, while in Gladis the Si treatment did not significantly change the measured parameters.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Silício/farmacologia , Síncrotrons , Estresse Oxidativo , Perfilação da Expressão Gênica
13.
Molecules ; 27(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36364034

RESUMO

Biochemical investigations were carried out on the embalmed head of Nebiri (Museo Egizio, Turin; S-5109)-an 18th Dynasty Ancient Egyptian dignitary-and on the canopic jar containing his lungs (Museo Egizio, Turin; S. 5111/02) with the aim of characterizing the organ's (lung) specific paleo-proteins and of identifying the compounds used in his embalming "recipe". The application of a functionalized film method allowed us to perform a non-invasive sampling. Paleo-proteomics confirmed the presence of lung tissue-specific proteins (organ specific) as well as the presence of proteins linked to severe inflammation. Paleoproteomics and paleometabolomics further allowed the identification of the main components of Nebiri's embalming recipe: animal fats and glue, balms, essential oils, aromatic plants, heated Pistacia, and coniferous resins. Both the use of Pistacia and coniferous resins in an early 18th Dynasty individual confirm Nebiri's high social status. The technique applied offers a targeted approach to the chemical characterization of human tissues, embalming compounds, and organic materials layering in pottery. The ability of the functionalized film method to harvest all types of compounds, from macromolecules (i.e., proteins) to small molecules (i.e., organic acids) opens a new path in the study of ancient material culture; furthermore, it allows to perform untargeted analysis, which is necessary when no a priori information is available.


Assuntos
Múmias , Pistacia , Animais , Humanos , História Antiga , Proteômica , Embalsamamento/métodos , Metabolômica , Resinas Vegetais
14.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36142664

RESUMO

Non-thermal plasma technology is increasingly being applied in the plant biology field. Despite the variety of beneficial effects of plasma-activated water (PAW) on plants, information about the mechanisms of PAW sensing by plants is still limited. In this study, in order to link PAW perception to the positive downstream responses of plants, transgenic Arabidopsis thaliana seedlings expressing the Ca2+-sensitive photoprotein aequorin in the cytosol were challenged with water activated by low-power non-thermal plasma generated by a dielectric barrier discharge (DBD) source. PAW sensing by plants resulted in the occurrence of cytosolic Ca2+ signals, whose kinetic parameters were found to strictly depend on the operational conditions of the plasma device and thus on the corresponding mixture of chemical species contained in the PAW. In particular, we highlighted the effect on the intracellular Ca2+ signals of low doses of DBD-PAW chemicals and also presented the effects of consecutive plant treatments. The results were discussed in terms of the possibility of using PAW-triggered Ca2+ signatures as benchmarks to accurately modulate the chemical composition of PAW in order to induce environmental stress resilience in plants, thus paving the way for further applications in agriculture.


Assuntos
Equorina , Arabidopsis , Cálcio/farmacologia , Cálcio da Dieta/farmacologia , Citosol , Água/farmacologia
15.
Sci Technol Adv Mater ; 23(1): 76-119, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309252

RESUMO

The over-dependence on fossil fuels is one of the critical issues to be addressed for combating greenhouse gas emissions. Hydrogen, one of the promising alternatives to fossil fuels, is renewable, carbon-free, and non-polluting gas. The complete utilization of hydrogen in every sector ranging from small to large scale could hugely benefit in mitigating climate change. One of the key aspects of the hydrogen sector is its production via cost-effective and safe ways. Electrolysis and photocatalysis are well-known processes for hydrogen production and their efficiency relies on electrocatalysts, which are generally noble metals. The usage of noble metals as catalysts makes these processes costly and their scarcity is also a limiting factor. Metal nitrides and their porous counterparts have drawn considerable attention from researchers due to their good promise for hydrogen production. Their properties such as active metal centres, nitrogen functionalities, and porous features such as surface area, pore-volume, and tunable pore size could play an important role in electrochemical and photocatalytic hydrogen production. This review focuses on the recent developments in metal nitrides from their synthesis methods point of view. Much attention is given to the emergence of new synthesis techniques, methods, and processes of synthesizing the metal nitride nanostructures. The applications of electrochemical and photocatalytic hydrogen production are summarized. Overall, this review will provide useful information to researchers working in the field of metal nitrides and their application for hydrogen production.

16.
Sci Technol Adv Mater ; 23(1): 66-75, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125966

RESUMO

Stimuli-responsive polymers with complicated but controllable shape-morphing behaviors are critically desirable in several engineering fields. Among the various shape-morphing materials, cross-linked polymers with exchangeable bonds in dynamic network topology can undergo on-demand geometric change via solid-state plasticity while maintaining the advantageous properties of cross-linked polymers. However, these dynamic polymers are susceptible to creep deformation that results in their dimensional instability, a highly undesirable drawback that limits their service longevity and applications. Inspired by the natural ice strategy, which realizes creep reduction using crystal structure transformation, we evaluate a dynamic cross-linked polymer with tunable creep behavior through topological alternation. This alternation mechanism uses the thermally triggered disulfide-ene reaction to convert the network topology - from dynamic to static - in a polymerized bulk material. Thus, such a dynamic polymer can exhibit topological rearrangement for thermal plasticity at 130°C to resemble typical dynamic cross-linked polymers. Following the topological alternation at 180°C, the formation of a static topology reduces creep deformation by more than 85% in the same polymer. Owing to temperature-dependent selectivity, our cross-linked polymer exhibits a shape-morphing ability while enhancing its creep resistance for dimensional stability and service longevity after sequentially topological alternation. Our design enriches the design of dynamic covalent polymers, which potentially expands their utility in fabricating geometrically sophisticated multifunctional devices.

17.
Sci Technol Adv Mater ; 22(1): 758-771, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34566493

RESUMO

A novel heterogeneous catalytic nanomaterial based on a molybdenum cluster-based halide (MC) and a single-layered copper hydroxynitrate (CHN) was first prepared by colloidal processing under ambient conditions. The results of the elemental composition and crystalline pattern indicated that CHN was comprehensively synthesized with the support of the MC compound. The absorbing characteristic in the ultraviolet and near-infrared regions was promoted by both of the ingredients. The proper chemical interaction between the materials is a crucial reason to modify the structure of the MCs and only a small decrease in the magnetic susceptibility of CHN. The heterogeneous catalytic activity of the obtained MC@CHN material was found to have a high efficiency and excellent reuse when it is activated by hydrogen peroxide (H2O2) for the degrading reaction of the organic pollutant at room temperature. A reasonable catalytic mechanism was proposed to explain the distinct role of the copper compound, Mo6 compound, and H2O2 in the production of the radical hydroxyl ion. This novel nanomaterial will be an environmentally promising candidate for dye removal.

18.
Microorganisms ; 9(7)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34361960

RESUMO

Prokaryotic communities and physico-chemical characteristics of 30 brine samples from the thalassohaline Tuz Lake (Salt Lake), Deep Zone, Kayacik, Kaldirim, and Yavsan salterns (Turkey) were analyzed using 16S rRNA amplicon sequencing and standard methods, respectively. Archaea (98.41% of reads) was found to dominate in these habitats in contrast to the domain Bacteria (1.38% of reads). Representatives of the phylum Euryarchaeota were detected as the most predominant, while 59.48% and 1.32% of reads, respectively, were assigned to 18 archaeal genera, 19 bacterial genera, 10 archaeal genera, and one bacterial genus that were determined to be present, with more than 1% sequences in the samples. They were the archaeal genera Haloquadratum, Haloarcula, Halorhabdus, Natronomonas, Halosimplex, Halomicrobium, Halorubrum, Halonotius, Halolamina, Halobacterium, and Salinibacter within the domain Bacteria. The genera Haloquadratum and Halorhabdus were found in all sampling sites. While Haloquadratum, Haloarcula, and Halorhabdus were the most abundant genera, two uncultured Tuz Lake Halobacteria (TLHs) 1 and 2 were detected in high abundance, and an additional uncultured haloarchaeal TLH-3 was found as a minor abundant uncultured taxon. Their future isolation in pure culture would permit us to expand our knowledge on hypersaline thalassohaline habitats, as well as their ecological role and biomedical and biotechnological potential applications.

19.
Sci Technol Adv Mater ; 22(1): 373-385, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34104117

RESUMO

Phase equilibria among the η-Fe2Al5 phase and its higher-ordered phases with the η framework structure were determined experimentally. The solubility range of the η phase at elevated temperature does not differ remarkably from that in previous studies, but this phase is found to undergo complicated phase transformations upon cooling. Four phases are present, namely η', η", η"' and η m, with higher-order atomic orderings in the c-axis chain sites of the orthorhombic crystal structure of the parent η phase. The η" and η"' phases form on the Al-poor and Al-rich sides, respectively, in equilibrium with the ζ-FeAl2 phase below ~415°C and θ-Fe4Al13 phase below ~405°C. The η' and η m phases become stable below 312°C and 343°C with the peritectoid reactions η' → η m + Î·"' and η m → η + Î·", respectively. The η phase is not stable below 331°C with the eutectoid reaction of η m + Î·"' → η. On the basis of these findings, we unraveled the phase equilibria among the η-Fe2Al5 phase and its higher-ordered phases with the η framework structure.

20.
Sci Technol Adv Mater ; 22(1): 194-204, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33907525

RESUMO

Shortwave infrared (SWIR) optical sensing and imaging are essential to an increasing number of next-generation applications in communications, process control or medical imaging. An all-organic SWIR upconversion device (OUC) consists of an organic SWIR sensitive photodetector (PD) and an organic light-emitting diode (OLED), connected in series. OUCs directly convert SWIR to visible photons, which potentially provides a low-cost alternative to the current inorganic compound-based SWIR imaging technology. For OUC applications, only few organic materials have been reported with peak absorption past 1000 nm and simultaneous small absorption in the visible. Here, we synthesized a series of thermally stable high-extinction coefficient donor-substituted benz[cd]indole-capped SWIR squaraine dyes. First, we coupled the phenyl-, carbazole-, and thienyl-substituted benz[cd]indoles with squaric acid (to obtain the SQ dye family). We then combined these donors with the dicyanomethylene-substituted squaraine acceptor unit, to obtain the dicyanomethylene-functionalized squaraine DCSQ family. In the solid state, the absorbance of all dyes extended considerably beyond 1100 nm. For the carbazole- and thienyl-substituted DCSQ dyes, even the peak absorptions in solution were in the SWIR, at 1008 nm and 1014 nm. We fabricated DCSQ PDs with an external photon-to-current efficiency over 30%. We then combined the PD with a fluorescent OLED and fabricated long-term stable OUCs with peak sensitivity at 1020 nm, extending to beyond 1200 nm. Our OUCs are characterized by a very low dark luminance (<10-2 cd m-2 at below 6 V) in the absence of SWIR light, and a low turn-on voltage of 2 V when SWIR light is present.

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