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1.
Sci Data ; 11(1): 367, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605060

RESUMO

Coral reefs support the world's most diverse marine ecosystem and provide invaluable goods and services for millions of people worldwide. They are however experiencing frequent and intensive marine heatwaves that are causing coral bleaching and mortality. Coarse-grained climate models predict that few coral reefs will survive the 3 °C sea-surface temperature rise in the coming century. Yet, field studies show localized pockets of coral survival and recovery even under high-temperature conditions. Quantifying recovery from marine heatwaves is central to making accurate predictions of coral-reef trajectories into the near future. Here we introduce the world's most comprehensive database on coral recovery following marine heatwaves and other disturbances, called Heatwaves and Coral-Recovery Database (HeatCRD) encompassing 29,205 data records spanning 44 years from 12,266 sites, 83 countries, and 160 data sources. These data provide essential information to coral-reef scientists and managers to best guide coral-reef conservation efforts at both local and regional scales.


Assuntos
Antozoários , Recifes de Corais , Animais , Ecossistema , Temperatura , Mudança Climática
2.
J Esthet Restor Dent ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623067

RESUMO

OBJECTIVES: This study was aimed to obtain an experimental bleaching agent by adding casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) in order to eliminate the mineral loss on the tooth surface after bleaching and to evaluate the bleaching effectiveness. MATERIALS AND METHODS: In this study, experimental bleaching agents containing 1%, 3% CPP-ACP and without CPP-ACP were obtained. Bleaching effectiveness (color change), the effect of bleaching agents on mineral content (energy dispersive x-ray spectroscopy), surface morphology (scanning electron microscope), and surface hardness of enamel (Vicker's microhardness) before and after bleaching were evaluated. The obtained data were statistically analyzed. RESULTS: When the bleaching levels of the groups were compared, no statistically significant difference was observed between the control and 1% CPP-ACP groups (p > 0.05) while the addition of 3% CPP-ACP decreased significantly the effectiveness of the bleaching agent (p < 0.05). When the effects of experimental bleaching agents on surface hardness were examined, while the enamel surface hardness decreased statistically significantly after application in the control group (p < 0.05), no statistically significant change was observed in surface hardness after the application of 1% CPP-ACP containing bleaching agent (p > 0.05). However, a statistically significant increase was observed in surface hardness after the application of 3% CPP-ACP containing bleaching agent (p < 0.05). When the Ca and P ratio of the groups were compared, no statistically significant difference was observed between the control and 1% CPP-ACP groups (p > 0.05), while they increased significantly in 3% CPP-ACP group (p < 0.05). CONCLUSIONS: The addition of 1% CPP-ACP to the bleaching agent had positive effects on the mineral content and surface hardness of the enamel, and did not negatively affect the whitening effectiveness. CLINICAL SIGNIFICANCE: Adding CPP-ACP to the bleaching agent at appropriate concentrations can eliminate possible negative effects without compromising the effectiveness of the bleaching agent.

3.
Oper Dent ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632866

RESUMO

OBJECTIVES: This study evaluated the influence of hydrogen peroxide (HP) with or without titanium dioxide nanotubes (TiO2) associated with violet LED (VL) regarding: a) the temperature change in the pulp chamber and facial surface; b) the decomposition of HP; and c) the cytotoxicity of the gels on pulp cells. METHODS AND MATERIALS: The experimental groups were: HP35 (35% HP/Whiteness HP, FGM); HP35+VL; HP35T (HP35+TiO2); HP35T+VL; HP7 (7.5% HP/White Class 7.5%, FGM); HP7+VL; HP7T (HP7+TiO2); and HP7T+VL. TiO2 was incorporated into the bleaching gels at 1%. Eighty bovine incisors were evaluated to determine temperature change in 8 experimental groups (n=10/group). A k-type thermocouple was used to evaluate the temperatures of the facial surface and in the pulp chamber, achieved by enabling endodontic access to the palatal surface, throughout the 30-minute session. HP decomposition (n=3) of gels was evaluated by using an automatic potentiometric titrator at the initial and 30-minute time points. Trans-enamel and trans-dentinal cell viability were assessed with a pulp chamber device as well as enamel and dentin discs (n=6), and the treatment extracts (culture medium + diffused components) were collected and applied to MDPC-23 odontoblast cells to evaluate cell viability according to the MTT test. RESULTS: A temperature increase in the pulp chamber was observed in the presence of VL at 30 minutes (p<0.05) (Mann-Whitney test). Also at 30 minutes, HP35 showed greater decomposition in the presence of VL rather than in its absence (p<0.05) (mixed linear models and the Tukey-Kramer test). HP7 provided greater cell viability than the groups treated with HP35 (p<0.05) (generalized linear models test). Cell viability was significantly lower for HP7 in the presence of VL (p<0.05). CONCLUSION: Pulpal temperature increased with VL (maximum of 1.9°C), but did not exceed the critical limit to cause pulp damage. Less concentrated HP resulted in higher cell viability, even when associated with VL.

4.
J Family Med Prim Care ; 13(2): 713-716, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38605752

RESUMO

Background: Cosmetic products may contain ingredients whose safety is not certain with several instances of death and anaphylaxis due to service/cosmetic usage in beauty salons. With the mushrooming of beauty salons and with a large consumer base, there is a dearth in the literature to assess the awareness of the health hazards among the employees. This study aims to measure the awareness levels on health hazards and their emergency management among employees working in beauty salons in Coimbatore. Materials and Methods: A cross-sectional study using a semi-structured questionnaire, after Institutional Human Ethics Committee (IHEC) approval, was conducted*** to assess the awareness of the health hazards including emergency management among employees of beauty salons. The sample size was estimated to be 160. All the workers working in unisex beauty salons, selected by convenience sampling within 5 km radius of PSG IMS and R, were assessed based on their awareness toward cosmetics and the data were analyzed using SPSS software version 24 (IBM SPSS Statistics for Windows, Version 24.0. Armonk, NY). Results: Around 160 service providers of beauty salons participated in the study, among which 84% use several cosmetic products. Only 40% are aware of the health impacts and 21.3% are aware about the side effects which included rashes and itching associated with the products used for bleaching. Only 36.9% knew about the regulations for usage of cosmetic products and 30% knew that there is a governing body for the same. Conclusion: Awareness of health hazards and its emergency management is less among the workers; the literacy programs to improve the awareness on use of cosmetics is the need of the hour.

5.
Curr Biol ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38608678

RESUMO

Coral reefs are a biodiversity hotspot,1,2 and the association between coral and intracellular dinoflagellates is a model for endosymbiosis.3,4 Recently, corals and related anthozoans have also been found to harbor another kind of endosymbiont, apicomplexans called corallicolids.5 Apicomplexans are a diverse lineage of obligate intracellular parasites6 that include human pathogens such as the malaria parasite, Plasmodium.7 Global environmental sequencing shows corallicolids are tightly associated with tropical and subtropical reef environments,5,8,9 where they infect diverse corals across a range of depths in many reef systems, and correlate with host mortality during bleaching events.10 All of this points to corallicolids being ecologically significant to coral reefs, but it is also possible they are even more widely distributed because most environmental sampling is biased against parasites that maintain a tight association with their hosts throughout their life cycle. We tested the global distribution of corallicolids using a more direct approach, by specifically targeting potential anthozoan host animals from cold/temperate marine waters outside the coral reef context. We found that corallicolids are in fact common in such hosts, in some cases at high frequency, and that they infect the same tissue as parasites from topical coral reefs. Parasite phylogeny suggests corallicolids move between hosts and habitats relatively frequently, but that biogeography is more conserved. Overall, these results greatly expand the range of corallicolids beyond coral reefs, suggesting they are globally distributed parasites of marine anthozoans, which also illustrates significant blind spots that result from strategies commonly used to sample microbial biodiversity.

6.
Int Dent J ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38614882

RESUMO

AIM: This study aimed to identify the optimal toothpaste for removing coffee-induced stains while also evaluating its impact on tooth enamel through roughness and abraded depth parameters, providing a comprehensive understanding of their effects. MATERIALS AND METHODS: Three whitening toothpastes and 2 conventional toothpastes were prepared for a simulated brushing procedure on coffee-stained bovine enamel tooth specimens. Using a toothbrushing machine, up to 10,000 brushstrokes were completed, while spectrophotometric readings were taken at designated intervals. A mixed-effects model for statistical analysis determined the effects of toothpaste and brushing on colour change, roughness, and abraded depth. RESULTS: Whitening toothpastes significantly deviated from the control (P < .001, P < .001, and P < .003, respectively), whereas the conventional toothpaste did not exhibit a significant contrast (P < .081). Regarding colour restoration following coffee staining, whitening toothpastes showed higher restoration than conventional toothpastes. Surface roughness and abraded depth parameters increased with accumulated brushing. CONCLUSIONS: Sodium hexametaphosphate-containing toothpaste demonstrated the highest efficacy in removing coffee-induced stains and restoring tooth colour. Nevertheless, this stronger whitening effect was associated with increased abrasion. While conventional toothpastes exhibited some whitening effects, the most substantial improvement in lightness was consistently observed with whitening toothpastes. CLINICAL RELEVANCE: Understanding how whitening toothpaste affects enamel integrity is crucial for refining formulations and advancing dental care. This knowledge lays the groundwork for more effective oral care products and improved whitening procedures, ultimately enhancing the overall quality of dental treatments.

7.
BMC Oral Health ; 24(1): 445, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609921

RESUMO

BACKGROUND: Considering the extensive use of bleaching agents and the occurrence of side effects such as enamel demineralization, this study aimed to assess the enamel changes of bleached teeth following the experimental application of chitosan-bioactive glass (CH-BG). METHODS: In this in vitro study, CH-BG (containing 66% BG) was synthesized and characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Thirty sound human premolars were bleached with 40% hydrogen peroxide, and the weight% of calcium and phosphorus elements of the buccal enamel surface was quantified before and after bleaching by scanning electron microscopy/ energy-dispersive X-ray spectroscopy (SEM, EDX). Depending on the surface treatment of the enamel surface, the specimens were divided into three groups (n = 10): control (no treatment), MI Paste (MI), and CH-BG. Then the specimens were stored in artificial saliva for 14 days. The SEM/EDX analyses were performed again on the enamel surface. Data were analyzed by one-way ANOVA and Tukey's test and a p-value of < 0.05 was considered statistically significant. RESULTS: In all groups, the weight% of calcium and phosphorus elements of enamel decreased after bleaching; this reduction was significant for phosphorus (p < 0.05) and insignificant for calcium (p > 0.05). After 14 days of remineralization, the weight% of both calcium and phosphorus elements was significantly higher compared to their bleached counterparts in both MI and CH-BG groups (p < 0.05). Following the remineralization process, the difference between MI and CH-BG groups was not significant (p > 0.05) but both had a significant difference with the control group in this regard (p < 0.05). CONCLUSIONS: The synthesized CH-BG compound showed an efficacy comparable to that of MI Paste for enamel remineralization of bleached teeth.


Assuntos
Quitosana , Clareamento Dental , Humanos , Cálcio , Quitosana/efeitos adversos , Clareamento Dental/efeitos adversos , Esmalte Dentário , Fósforo
8.
Mol Plant Pathol ; 25(4): e13449, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619508

RESUMO

Pyricularia oryzae (syn. Magnaporthe oryzae), is a filamentous ascomycete that causes a major disease called blast on cereal crops, as well as on a wide variety of wild and cultivated grasses. Blast diseases have a tremendous impact worldwide particularly on rice and on wheat, where the disease emerged in South America in the 1980s, before spreading to Asia and Africa. Its economic importance, coupled with its amenability to molecular and genetic manipulation, have inspired extensive research efforts aiming at understanding its biology and evolution. In the past 40 years, this plant-pathogenic fungus has emerged as a major model in molecular plant-microbe interactions. In this review, we focus on the clarification of the taxonomy and genetic structure of the species and its host range determinants. We also discuss recent molecular studies deciphering its lifecycle. TAXONOMY: Kingdom: Fungi, phylum: Ascomycota, sub-phylum: Pezizomycotina, class: Sordariomycetes, order: Magnaporthales, family: Pyriculariaceae, genus: Pyricularia. HOST RANGE: P. oryzae has the ability to infect a wide range of Poaceae. It is structured into different host-specialized lineages that are each associated with a few host plant genera. The fungus is best known to cause tremendous damage to rice crops, but it can also attack other economically important crops such as wheat, maize, barley, and finger millet. DISEASE SYMPTOMS: P. oryzae can cause necrotic lesions or bleaching on all aerial parts of its host plants, including leaf blades, sheaths, and inflorescences (panicles, spikes, and seeds). Characteristic symptoms on leaves are diamond-shaped silver lesions that often have a brown margin and whose appearance is influenced by numerous factors such as the plant genotype and environmental conditions. USEFUL WEBSITES Resources URL Genomic data repositories http://genome.jouy.inra.fr/gemo/ Genomic data repositories http://openriceblast.org/ Genomic data repositories http://openwheatblast.net/ Genome browser for fungi (including P. oryzae) http://fungi.ensembl.org/index.html Comparative genomics database https://mycocosm.jgi.doe.gov/mycocosm/home T-DNA mutant database http://atmt.snu.kr/ T-DNA mutant database http://www.phi-base.org/ SNP and expression data https://fungidb.org/fungidb/app/.


Assuntos
Ascomicetos , Hordeum , Ascomicetos/genética , Produtos Agrícolas , Triticum
9.
ACS Appl Mater Interfaces ; 16(15): 19094-19102, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38571376

RESUMO

Due to the spontaneous transport of small-sized cations and redox reactions under open circuit conditions, the currently reported coloring electrochromic devices (ECDs) may self-bleach easily. The resulting ECDs exhibit poor open-circuit memory, which limits their applications in static display advertisement. By constructing energy barriers to effectively control small-sized cation transport, the redox reaction could be suppressed, thereby inhibiting the self-bleaching of ECDs. In this study, phosphate glass is used as an electrolyte to construct high-energy barriers. Sodium ions in phosphate glass absorb external heat to cross energy barriers and become conductive charge carriers. In this case, the electrochromism of ECDs is allowed. On the contrary, after the absorbed heat energy is released, sodium ions are immediately trapped by oxygen ions in the PO4 unit, becoming frozen ions. At this point, the electrochromization of ECDs is prohibited. Based on the ionic conductive feature of phosphate glass, ECDs absorb heat and are colored by applying an electric field first. Then, ECDs release the thermal energy and the sodium ions transport in the electrolyte is blocked to cut off the self-bleaching pathway. The prepared inorganic all-solid-state ECDs maintained the colored state for several months using the method mentioned above, which solved the problem of the poor open-circuit memory of ECDs.

10.
J Exp Biol ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563292

RESUMO

Concentrations of dissolved nitrogen in seawater can affect the resilience of the cnidarian-dinoflagellate symbiosis to climate change-induced bleaching. However, it is not yet known how the assimilation and translocation of the various nitrogen forms change during heat stress, nor how the symbiosis responds to nutrient depletion, which may be observed due to increasing water stratification. Here, the tropical scleractinian coral Stylophora pistillata, in symbiosis with dinoflagellates of the genus Symbiodinium, was grown at different temperatures (26°C, 30°C, and 34°C), before being placed in nutrient-replete or depleted seawater for 24 hours. The corals were then incubated with 13C-labelled sodium bicarbonate and different 15N-labelled nitrogen forms (ammonium, urea, and dissolved free amino acids) to determine their assimilation rates. We found that nutrient depletion inhibited the assimilation of all nitrogen sources studied and that heat stress reduced the assimilation of ammonium and dissolved free amino acids. However, the host assimilated over threefold more urea at 30°C relative to 26°C. Overall, both moderate heat stress (30°C) and nutrient depletion individually decreased the total nitrogen assimilated by the symbiont by 66%, and combined, they decreased assimilation by 79%. This led to the symbiotic algae becoming nitrogen starved, with the C:N ratio increasing over threefold at 34°C, potentially exacerbating the impacts of coral bleaching.

11.
Mar Pollut Bull ; 202: 116273, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38569302

RESUMO

Coral reefs are home to a variety of species, and their preservation is a popular study area; however, monitoring them is a significant challenge, for which the use of robots offers a promising answer. The purpose of this study is to analyze the current techniques and tools employed in coral reef monitoring, with a focus on the role of robotics and its potential in transforming this sector. Using a systematic review methodology examining peer-reviewed literature across engineering and earth sciences from the Scopus database focusing on "robotics" and "coral reef" keywords, the article is divided into three sections: coral reef monitoring, robots in coral reef monitoring, and case studies. The initial findings indicated a variety of monitoring strategies, each with its own advantages and disadvantages. Case studies have also highlighted the global application of robotics in monitoring, emphasizing the challenges and opportunities unique to each context. Robotic interventions driven by artificial intelligence and machine learning have led to a new era in coral reef monitoring. Such developments not only improve monitoring but also support the conservation and restoration of these vulnerable ecosystems. Further research is required, particularly on robotic systems for monitoring coral nurseries and maximizing coral health in both indoor and open-sea settings.

12.
Appl Opt ; 63(8): 1947-1951, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568633

RESUMO

Three samples whose growth temperatures were 450°C, 500°C, and 560°C for S E S A M 1, S E S A M 2, and S E S A M 3, respectively, were tested by femto-second time-resolved transient absorption spectroscopy. The results indicate that the carrier dynamics of excited state absorption were dominant, and the lifetimes of carriers trapped by defect levels were about tens of pico-seconds. To further study the influence of carrier dynamics and recovery time of samples by ion-implantation, B + ions of 80 and 130 KeV were implanted into the samples with dose of 1014/c m 2. The modified samples showed a dominance of ultra-fast carrier dynamics of ground-state bleaching and direct recombination, which lasted for hundreds of femto-seconds, over excited state absorption. Additionally, carrier fast trapping was observed to be competitive with the excited state absorption process. After ion-implantation, the carrier dynamics of carrier trapping were enhanced, which contributed to forming an ultra-short laser, while the carrier dynamics of absorption of the excited state were suppressed. The conclusion that defect levels were partially eliminated by B + ion-implantation can be drawn.

13.
Evid Based Dent ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605151

RESUMO

OBJECTIVE: Discolouration of primary teeth, often attributed to trauma and pulpal infection, is a prevalent concern that can significantly impact the esthetics and self-esteem of children. To address this issue, bleaching techniques have emerged as a viable treatment option. This systematic review aims to provide a comprehensive summary of the effectiveness of bleaching agents in managing discoloured primary teeth. METHODS: Two reviewers independently conducted an electronic database search using PubMed, EMBASE, LILACS, CINAHL via EBSCO, Scopus, and Web of Science until September 26,2023. In vitro studies and case reports that assessed the quantifiable success were included. The present review utilized Distiller SR software for data extraction. The protocol of this study was registered in PROSPERO (International Prospective Register of Systematic Reviews) (CRD42022329831). The quality of studies was analysed with Cochrane tool and the JBI checklist. RESULTS: The search retrieved 1845 references of which 14 studies were included for qualitative analysis. There were 8 in vitro studies and 6 case reports included in this systematic review. There were 299 teeth samples in the in vitro studies and 18 teeth were assessed in the case reports. All the 18 teeth (6 case reports) showed considerable shade improvement within 7-14 days. However, only 3 teeth were followed up for a period of 12-24 months. Substantial shade improvement was also observed in samples in the in vitro studies. CONCLUSION: This systematic review has comprehensively examined the various bleaching agents and methods for the management of discoloured primary teeth. However, it is crucial to recognize that the available evidence is from case reports and is insufficient to make a clinical recommendation.

14.
J Chem Phys ; 160(14)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38597312

RESUMO

Electronic relaxation dynamics of solution-phase redox-exfoliated molybdenum disulfide (MoS2) monolayer and multilayer ensembles are described. MoS2 was exfoliated using polyoxometalate (POM) reductants. This process yields a colloidal heterostructure consisting of MoS2 2D sheet multilayers with surface-bound POM complexes. Using two-dimensional electronic spectroscopy, transient bleaching and photoinduced absorption signals were detected at excitation/detection energies of 1.82/1.87 and 1.82/1.80 eV, respectively. Approximate 100-fs bandgap renormalization (BGR) and subsequent defect- and phonon-mediated relaxation on the picosecond timescale were resolved for several MoS2 thicknesses spanning from 1 to 2 L to ∼20 L. BGR rates were independent of sample thickness and slightly slower than observations for chemical vapor deposition-grown MoS2 monolayers. However, defect-mediated relaxation accelerated ∼10-fold with increased sample thicknesses. The relaxation rates increased from 0.33 ± 0.05 to 1.2 ± 0.1 and 3.1 ± 0.4 ps-1 for 1-2 L, 3-4 L, and 20 L fractions. The thicknesses-dependent relaxation rates for POM-MoS2 heterostructures were modeled using a saturating exponential function that showed saturation at thirteen MoS2 layers. The results suggest that the increased POM surface coverage leads to larger defect density in the POM-MoS2 heterostructure. These are the first descriptions of the influence of sample thickness on electronic relaxation rates in solution-phase redox-exfoliated POM-MoS2 heterostructures. Outcomes of this work are expected to impact the development of solution-phase exfoliation of 2D metal-chalcogenide heterostructures.

15.
J Pharm Bioallied Sci ; 16(Suppl 1): S156-S158, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595474

RESUMO

Introduction: The application of the antioxidants after the teeth are bleached has been advocated to fasten the restorative process post-bleaching. The motive of this study was to examine and assess the micro-tensile binding strength of bleached enamel to the resin using a variety of antioxidant solutions. Finding the reason for the tooth fracture was the secondary outcome measured. Materials and Methods: An in vitro study was planned with 100 human extracted teeth, with 20 in each group with one as controls and 4 others tested for the antioxidants sodium ascorbate, epigallocatechin gallate, chitosan, and proanthocyanidin application. The bond strength of bleached enamel to the resin was well as the failure type was assessed after the values were noted and compared using the ANOVA and Tukey's methods keeping P < 0.05 as significant. Results: Epigallocatechin gallate specimens displayed the maximum micro-tensile bond strength under the investigational circumstances, whereas controls displayed the lowest micro-tensile bond strength. There was statistical alteration in micro-tensile bond strengths between all the groups except between epigallocatechin gallate vs chitosan and sodium ascorbate vs proanthocyanidin. High statistical significance was seen between the control and the antioxidant groups as well as between sodium ascorbate and epigallocatechin gallate and chitosan. Conclusion: The antioxidant chemicals significantly augmented the bond strength of bleached enamel to the resin that had been bleached. Also, when compared to the other experimental groups, epigallocatechin gallate and chitosan treatment displayed the greatest mean bond strength values.

16.
Front Plant Sci ; 15: 1350405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576792

RESUMO

Naturally colored cotton (NCC) offers an environmentally friendly fiber for textile applications. Processing white cotton fiber into textiles requires extensive energy, water, and chemicals, whereas processing of NCC skips the most polluting activity, scouring-bleaching and dyeing; therefore, NCC provides an avenue to minimize the harmful impacts of textile production. NCC varieties are suitable for organic agriculture since they are naturally insect and disease-resistant, salt and drought-tolerant. Various fiber shades, ranging from light green to tan and brown, are available in the cultivated NCC (Gossypium hirsutum L.) species. The pigments responsible for the color of brown cotton fiber are proanthocyanidins or their derivatives synthesized by the flavonoid pathway. Due to pigments, the NCC has excellent ultraviolet protection properties. Some brown cotton varieties exhibited superior thermal resistance of fiber that can be used to make fabrics with enhanced flame retardancy. Here, we review molecular mechanisms involved in the pigment production of brown cotton and challenges in breeding NCC varieties with a wide range of colors but without penalty in fiber quality. Also, we discuss opportunities for NCC with flame-retarding properties in textile applications.

17.
Nano Lett ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588010

RESUMO

Hampered by their susceptibility to nucleophilic attack and chemical bleaching, electron-deficient squaraine dyes have long been considered unsuitable for biological imaging. This study unveils a surprising twist: in aqueous environments, bleaching is not irreversible but rather a reversible spontaneous quenching process. Leveraging this new discovery, we introduce a novel deep-red squaraine probe tailored for live-cell super-resolution imaging. This probe enables single-molecule localization microscopy (SMLM) under physiological conditions without harmful additives or intense lasers and exhibits spontaneous blinking orchestrated by biological nucleophiles, such as glutathione or hydroxide anion. With a low duty cycle (∼0.1%) and high-emission rate (∼6 × 104 photons/s under 400 W/cm2), the squaraine probe surpasses the benchmark Cy5 dye by 4-fold and Si-rhodamine by a factor of 1.7 times. Live-cell SMLM with the probe reveals intricate structural details of cell membranes, which demonstrates the high potential of squaraine dyes for next-generation super-resolution imaging.

18.
Int J Biol Macromol ; 267(Pt 1): 131444, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588840

RESUMO

Ramie bone (RB), an agricultural waste generated in the textile industry, is a vastly productive renewable natural resource with the potential to be used as a source of cellulose. In this study, ramie bone cellulose (RB-CE) was obtained in one step using a simple and ecologically friendly hydrogen peroxide-citric acid (HPCA) treatment procedure that avoided the use of halogenated reagents and strong acids while also streamlining the treatment processes. Various analytical methods were used to investigate the chemical composition and structure, crystallinity, morphology, thermal properties, surface area and hydration properties of cellulose separated at different treatment temperatures. HPCA successfully removed lignin and hemicellulose from RB, according to chemical composition analysis and FTIR. RB-CE had a type I cellulose crystal structure, and the crystallinity improved with increasing treatment temperature, reaching 72.51 % for RB-CE90. The RB-CE showed good thermal stability with degradation temperatures ranging from 294.2 °C to 319.1 °C. Furthermore, RB-CE had a high water/oil binding capacity, with RB-CE90 having WHC and OBC of 9.68 g/g and 7.24 g/g, respectively. The current work serves as a model for the environmentally friendly and convenient extraction of cellulose from biomass, and the cellulose obtained can be employed in the field of food and composite materials.

19.
Mol Ecol ; 33(9): e17342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38584356

RESUMO

Endosymbiotic dinoflagellates (Symbiodiniaceae) influence coral thermal tolerance at both local and regional scales. In isolation, the effects of host genetics, environment, and thermal disturbances on symbiont communities are well understood, yet their combined effects remain poorly resolved. Here, we investigate Symbiodiniaceae across 1300 km in Australia's Coral Sea Marine Park to disentangle these interactive effects. We identified Symbiodiniaceae to species-level resolution for three coral species (Acropora cf humilis, Pocillopora verrucosa, and Pocillopora meandrina) by sequencing two genetic markers of the symbiont (ITS2 and psbAncr), paired with genotype-by-sequencing of the coral host (DArT-seq). Our samples predominantly returned sequences from the genus Cladocopium, where Acropora cf humilis affiliated with C3k, Pocillopora verrucosa with C. pacificum, and Pocillopora meandrina with C. latusorum. Multivariate analyses revealed that Acropora symbionts were driven strongly by local environment and thermal disturbances. In contrast, Pocillopora symbiont communities were both partitioned 2.5-fold more by host genetic structure than by environmental structure. Among the two Pocillopora species, the effects of environment and host genetics explained four times more variation in symbionts for P. meandrina than P. verrucosa. The concurrent bleaching event in 2020 had variable impacts on symbiont communities, consistent with patterns in P. verrucosa and A. cf humilis, but not P. meandrina. Our findings demonstrate how symbiont macroscale community structure responses to environmental gradients depend on host species and their respective population structure. Integrating host, symbiont, and environmental data will help forecast the adaptive potential of corals and their symbionts amidst a rapidly changing environment.

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