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1.
J Environ Sci (China) ; 150: 332-339, 2025 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39306408

RESUMEN

NH3-SCR (SCR: Selective catalytic reduction) is an effective technology for the de-NOx process from both mobile and stationary pollution sources, and the most commonly used catalysts are the vanadia-based catalysts. An innovative V2O5-CeO2/TaTiOx catalyst for NOx removal was prepared in this study. The influences of Ce and Ta in the V2O5-CeO2/TaTiOx catalyst on the SCR performance and physicochemical properties were investigated. The V2O5-CeO2/TaTiOx catalyst not only exhibited excellent SCR activity in a wide temperature window, but also presented strong resistance to H2O and SO2 at 275 ℃. A series of characterization methods was used to study the catalysts, including H2-temperature programmed reduction, X-ray photoelectron spectroscopy, NH3-temperature programmed desorption, etc. It was discovered that a synergistic effect existed between Ce and Ta species. The introduction of Ce and Ta enlarged the specific surface area, increased the amount of acid sites and the ratio of Ce3+, (V3++V4+) and Oα, and strengthened the redox capability which were related to synergistic effect between Ce and Ta species, significantly improving the NH3-SCR activity.


Asunto(s)
Amoníaco , Cerio , Titanio , Compuestos de Vanadio , Catálisis , Cerio/química , Titanio/química , Amoníaco/química , Compuestos de Vanadio/química , Contaminantes Atmosféricos/química , Oxidación-Reducción , Contaminación del Aire/prevención & control
2.
Food Chem ; 462: 140973, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39208730

RESUMEN

High-pressure processing (HPP) of donor human milk (DM) minimally impacts the concentration and bioactivity of some important bioactive proteins including lactoferrin, and bile salt-stimulated lipase (BSSL) compared to Holder pasteurization (HoP), yet the impact of HPP and subsequent digestion on the full array of proteins detectable by proteomics remains unclear. We investigated how HPP impacts undigested proteins in DM post-processing and across digestion by proteomic analysis. Each pool of milk (n = 3) remained raw, or was treated by HPP (500 MPa, 10 min) or HoP (62.5 °C, 30 min), and underwent dynamic in vitro digestion simulating the preterm infant. In the meal, major proteins were minimally changed post-processing. HPP-treated milk proteins better resisted proximal digestion (except for immunoglobulins, jejunum 180 min) and the extent of undigested proteins after gastric digestion of major proteins in HPP-treated milk was more similar to raw (e.g., BSSL, lactoferrin, macrophage-receptor-1, CD14, complement-c3/c4, xanthine dehydrogenase) than HoP.


Asunto(s)
Digestión , Recien Nacido Prematuro , Proteínas de la Leche , Leche Humana , Pasteurización , Proteómica , Humanos , Leche Humana/química , Leche Humana/metabolismo , Proteínas de la Leche/metabolismo , Proteínas de la Leche/química , Proteínas de la Leche/análisis , Presión , Recién Nacido , Lactoferrina/análisis , Lactoferrina/metabolismo , Manipulación de Alimentos , Femenino , Lactante , Modelos Biológicos
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124945, 2025 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-39163768

RESUMEN

Pd speciation induced by the combined effect of CO and water on Pd/SSZ-13 samples prepared by both impregnation and ion exchange was examined by FT-IR spectroscopy of CO adsorbed at room temperature and at liquid nitrogen temperature on anhydrous and hydrated samples. Starting from the literature findings related to the CO reducing effect on Pd cations, the present work gives precise spectroscopic evidences on how water is necessary in this process not only for compensating with H+ the zeolite exchange sites set free by Pd reduction, but also for mobilizing isolated Pd2+/Pd+ cations and making possible the reduction reactions. The aggregation of some Pd+ sites, just formed by the reduction and mobilized by the hydration, gives rise to the formation of Pd2O particles. Also, Pd0(100) sites are observed with CO on hydrated sample, formed by the aggregation and reduction of isolated Pd cations. Moreover, Pd0(111) sites are formed on the surface of PdOx particles during CO outgassing. The observation of the combined effect of water and CO allowed to define assignments of IR bands related to carbonyls of Pd in different oxidation states and coordination degrees.

4.
Bioresour Technol ; 414: 131574, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39378533

RESUMEN

Cupric ions can restrain biological nitrogen removal processes, which comprise nitrite reductase and nitric oxide reductase. Here, Pseudomonas sp. NY1 can efficiently perform heterotrophic nitrification and aerobic denitrification with cupric ions at 15 °C. At optimal culturing conditions, low cupric ion levels accelerated nitrogen degradation, and ammonium and nitrite removal efficiencies increased by 2.33%-4.85% and 6.76%-12.30%, respectively. Moreover, the maximum elimination rates for ammonium and nitrite increased from 9.48 to 10.26 mg/L/h and 6.20 to 6.80 mg/L/h upon adding 0.05 mg/L cupric ions. Additionally, low cupric ion concentrations promoted electron transport system activity (ETSA), especially for nitrite reduction. However, high concentrations of cupric ions decreased the ETSA during nitrogen conversion processes. The crucial enzymes ammonia monooxygenase, nitrate reductase, and nitrite reductase possessed similarly trends as ETSA upon exposure to cupric ion. These findings deepen the understanding for the effect of cupric ions on nitrogen consumption and bioremediation in nitrogen-polluted waters.

5.
Proc Natl Acad Sci U S A ; 121(43): e2308684121, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39388277

RESUMEN

The aqueous alteration of the oceanic lithosphere provides significant energy that impacts the synthesis and diversity of organic compounds, which are crucial for the deep carbon cycle and may have provided the first building blocks for life. Although abiotic organic synthesis has been documented in mantle-derived rocks, the formation mechanisms and complexity of organic compounds in crustal rocks remain largely unknown. Here, we show the specific association of aliphatic carbonaceous matter with Fe oxyhydroxides in mafic crustal rocks of the Southwest Indian Ridge (SWIR). We determine potential Fe-based pathways for abiotic organic synthesis from CO2 and H2 using multimodal and molecular nano-geochemical tools. Quantum mechanical modeling is further employed to constrain the catalytical activity of Fe oxyhydroxides, revealing that the catalytic cycle of hydrogen may play a key role in carbon-carbon bond formation. This approach offers the possibility of interpreting physicochemical organic formation and condensation mechanisms at an atomic scale. The findings expand our knowledge of the existence of abiotic organic carbon in the oceanic crustal rocks and emphasize the mafic oceanic crust of the SWIR as a potential site for low-temperature abiotic organic synthesis.

6.
Sci Total Environ ; 954: 176742, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39374702

RESUMEN

The increasing frequency and severity of low temperatures, and soil cadmium (Cd) pollution threaten food security. However, the interactive effects of Cd exposure and low temperatures on rice yield and quality, as well as the mechanisms of Cd absorption and translocation, remain unclear. In this study, two rice varieties were cultivated in soils with two Cd contamination levels (Cdhigh and Cdlow) and exposed to control (CT25) or lower temperatures of 20 °C (LT20) and 17 °C (LT17) during grain-filling stage. Results showed significant decreases in seed setting rate and grain weight, reduced head rice yield, and increased chalkiness due to low temperatures, particularly in Cdhigh soils. Compared to CT25, LT17 and LT20 increased Cd concentration by 37.6 % and accumulation by 14.8 % in grains grown in Cdhigh soils. Enhanced root activity and upregulation of OsNramp1 and OsNramp5 under both low-temperatures increased Cd levels in roots. Lower temperatures also decreased phytochelatins (PCs) and increased expression of OsHMA2 and OsCAL1, facilitating Cd transport and raising Cd levels in stems. Furthermore, upregulated OsHMA2, OsLCT1, and OsZIP7 in stems under low-temperatures promoted Cd transport to panicles. Overall, low temperatures during grain filling increased Cd uptake and translocation into rice grains, especially in high Cd contaminated soils, raising health risks. The study highlights the need to address climate change's impact on cadmium hazards in rice.

7.
BMC Genomics ; 25(1): 947, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39379802

RESUMEN

BACKGROUD: Elephant grass (Cenchrus purpureus) is a perennial forage grass characterized by tall plants, high biomass and wide adaptability. Low-temperature stress severely limits elephant grass biomass and geographic distribution. WRKY is one of the largest families of plant-specific transcription factors and plays important roles in plant resistance to low-temperature. However, the understanding of the WRKY family in grasses is limited. In this study, we conducted a genome-wide characterization of WRKY proteins in elephant grass, including gene structure, phylogeny, expression, conserved motif organization, and functional annotation, to identify key CpWRKY candidates involved in cold tolerance. RESULTS: In this study, a total of 176 WRKY genes were identified in elephant grass. It was found that 172 were unevenly distributed across its 14 chromosomes, while the remaining 4 genes were not anchored to any chromosome. The genes were classified into three groups based on their WRKY conserved domains and zinc finger motifs. There were 12, 8, 19, 27, 12, 18 and 80 CpWRKYs belonging to group I, group IIa, group IIb, group IIc, group IId, group IIe and group III, respectively. We hypothesized that the ancient subgroup IIc WRKY gene is the ancestor of all WRKY genes in elephant grass. Most CpWRKYs in the same group have similar structure and motif composition. A total of 169 duplicate gene pairs were identified, suggesting that segmental duplication might have contributed to the expansion of the CpWRKY gene family. Ka/Ks analysis revealed that most of the CpWRKYs were subjected to purifying selection during the evolution. It was also found that six genes (CpWRKY51, CpWRKY81, CpWRKY100, CpWRKY101, CpWRKY140 and CpWRKY143) exhibited higher expression in roots compare to leaves, and were significantly induced by low temperature stress. Among them, CpWRKY81 had the highest expression under low-temperature stress, and its over-expression significantly enhanced the cold tolerance in yeast. CONLUSIONS: In this study, we characterized WRKY genes in elephant grass and further investigated their physicochemical properties, evolution, and expression patterns under low-temperature stress. This research provides valuable resources for identifying key CpWRKY genes that contribute to cold tolerance in elephant grass.


Asunto(s)
Familia de Multigenes , Filogenia , Proteínas de Plantas , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Frío , Cenchrus/genética , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Respuesta al Choque por Frío/genética , Estrés Fisiológico/genética
8.
BMC Plant Biol ; 24(1): 937, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39385096

RESUMEN

Low temperature is one of the environmental factors that restrict the growth and geographical distribution of Brassica. To investigate the effects of exogenous calcium and calcium inhibitor on the ability of winter turnip rapeseed (Brassica rapa L.) to withstand low temperatures (4℃), we used a strong cold-resistant variety Longyou 7 (L7) and a weak cold-resistant variety Longyou 99 (L99) as the materials. The seedlings were treated with CaCl2 (20 mmol·L-1) and calcium inhibitor LaCl3 (10 mmol·L-1) at 0 h (CK), 6 h, 12 h, 24 h and 48 h after 4℃ treatments. Physiological characteristics, Ca2+ flux and Ca2+ concentration in roots after treatments were analyzed. Results illustrated that under 4℃ treatment, activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) increased by both CK and exogenous CaCl2 treatments. Contents of soluble protein (SP) and proline (Pro) increased, while contents of malondialdehyde (MDA) decreased, resulting in reduced membrane lipid peroxidation. But enzyme activity decreased and MDA content increased following treatment with exogenous LaCl3. The rate of Ca2+ flow showed a higher uptake in L7 roots compared with L99. L99 showed Ca2+ efflux with a rate of 30.21 pmol‧cm-2‧s-1, whereas L7 showed short efflux then returned to influx. Calcium ion content in roots decreased in both cultivars after CaCl2 treatment. Results of RNA-seq revealed that genes were differentially expressed in response to low temperatures, hormones, photosystem II, chloroplasts, DNA replication, ribosomal RNA processing, and translation. This study found significant expression genes related to cellular signal transduction (MAPK signaling pathway) and material metabolism (nitrogen metabolism, glycerol ester metabolism).It was also analyzed by WGCNA that two modules had the strongest correlation with physiological indicators. Eight candidate genes were identified among MAPK signaling pathway and the two modules.


Asunto(s)
Brassica rapa , Calcio , Brassica rapa/efectos de los fármacos , Brassica rapa/genética , Brassica rapa/fisiología , Calcio/metabolismo , Frío , Plantones/efectos de los fármacos , Plantones/genética , Plantones/fisiología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Respuesta al Choque por Frío/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Cloruro de Calcio/farmacología
9.
Parasit Vectors ; 17(1): 418, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39369224

RESUMEN

BACKGROUND: The effects of low temperatures on parasitic wasps are crucial for maintaining farmland biodiversity and enhancing biological control, especially given the implications of global warming and frequent extreme cold events. METHODS: We studied the effects of different low temperatures (-8 ± 1 °C, -4 ± 1 °C, 0 ± 1 °C, 4 ± 1 °C, and 8 ± 1 °C) on the mating frequency and duration of male adults of Trichopria drosophilae and the number of pupae beaten by female adults, and constructed the age-stage two-sex life table of T. drosophilae. RESULTS: This study found that male T. drosophilae adults exposed to low temperatures for 12 h significantly altered their mating behavior, peaking between 15:00 and 17:00. As the temperature dropped during the exposure, both the mating frequency of T. drosophilae and the duration of pupal beating were affected. The survival rate of female adults dropped from 39.55% at 8 °C to just 21.17% at -8 °C. Low-temperature treatment shortened the development period and lifespan for T. drosophilae adults. They developed 4.71 days faster and had a total lifespan that was 10.66 days shorter than those in the control group after being exposed to -8 °C. Furthermore, the average number of eggs laid by females at -8 °C was 4.46 less than that at 8 °C and 6.16 less than that in the control group, which laid an average of 21.55 eggs. The net reproductive rate (R0) of T. drosophilae decreased with lower temperatures, reaching a low of 23.64 at -8 °C. Conversely, the intrinsic growth rate (rm) actually increased as temperatures dropped, with the lowest value being 0.21 at -8 °C. CONCLUSIONS: The findings indicate that short-term exposure to low temperatures hampers the growth and population increase of T. drosophilae, thereby reducing their effectiveness as biological control agents.


Asunto(s)
Frío , Tablas de Vida , Pupa , Avispas , Animales , Masculino , Femenino , Avispas/fisiología , Avispas/crecimiento & desarrollo , Pupa/crecimiento & desarrollo , Pupa/fisiología , Conducta Sexual Animal , Control Biológico de Vectores/métodos , Longevidad
10.
ChemSusChem ; : e202401728, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367689

RESUMEN

Low-temperature electroreduction of CO2 and CO (CO(2)RR) into valuable chemicals and fuels offers a promising pathway to reduce greenhouse gas emissions and achieve carbon neutrality. Today's low-temperature CO(2)RR technology relies on the use of ionomers, polymers with ionized groups, primarily as catalyst layer (CL) additives. In the meantime, ionomers can assemble into ion-exchange membranes (IEMs), serving as important components of electrolyzers. According to the ion-exchange functions, ionomer additives are classified as cation-exchange ionomers (CEIs) and anion-exchange ionomers (AEIs); similarly, IEMs are divided into cation-exchange membranes (CEMs) and anion-exchange membranes (AEMs), as well as the multilayer polymer electrolytes (MPEs). Recent studies show that ionomer additives can regulate the catalytic microenvironment and thereby enhance performance towards desired products. This Review discusses the roles of ionomer additives and IEMs in CO2 and CO reduction reactions, highlighting the latest mechanistic insights and performance advances. It outlines challenges in designing ionomer additives and IEMs to improve product selectivity, energy efficiency (EE), and operational lifetime of CO(2)RR electrolyzers, while also providing perspectives on future research directions. The aim is to connect the current status of ionomer and membrane development with performance metrics analysis, offering insights for the advancement of commercially relevant low-temperature CO(2)RR electrolyzers.

11.
Angew Chem Int Ed Engl ; : e202417988, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39382562

RESUMEN

Rational design of molecular structures is one of the effective strategies to obtain high-performance organic cathode materials. However, besides the optimization of single-molecule structures, the influence of the "weak" interaction forces (e.g. hydrogen bonds) in organic cathode materials on the performance of batteries should be fully considered. Herein, three organic small molecules with different numbers of hydroxyl groups (namely nitrogen heterocyclic tetraketone (DAB), monohydroxyl nitrogen heterocyclic dione (HDA), dihydroxyl nitrogen heterocyclic dione (DHT)) were selected as the cathodes of aqueous zinc ion batteries (AZIBs), and the effect of the intermolecular hydrogen bonds on their electrochemical performance was studied for the first time. Clearly, the stable hydrogen-bond networks built through the hydroxyl groups significantly enhance the cycle stability of organic small-molecule cathodes and facilitate rapid proton conduction between the hydrogen-bond networks through the Grotthuss mechanism, thereby endowing them with excellent rate performance. In addition, a larger and more dense two-dimensional hydrogen-bond network can be constructed through multiple hydroxyl groups, further enhancing the structural stability of organic small-molecule cathodes, giving them better cycle tolerance, excellent rate performance, and extreme environmental tolerance.

12.
Int J Biol Macromol ; 281(Pt 1): 136047, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39357708

RESUMEN

One of the main environmental stresses that considerably reduced vegetable yields are low temperature stress. Brassinosteroids (BRs) is essential for controlling a number of physiological functions. Protein S-nitrosylation is thought to be a crucial process in plants that use NO to carry out their biological functions. The exact process by which the mini Chinese cabbage responded to low temperature stress through BR-mediated S-nitrosylation modification of the monodehydroascorbate reductase (MDHAR) is still unknown. BR significantly increased the S-nitrosoylation level and antioxidant capacity at low temperature. One noteworthy development was the in vitroS-nitrosylation of the MDHAR protein. The overexpressed lines exhibited considerably high nitric oxide (NO) and S-nitrosothiol (SNO) contents at low temperature compared to the WT lines. Treatment of the WT and OE-BrMDHAR lines with BR at low temperature increased the antioxidant capacity. According to the biotin signaling, BR considerably enhanced the silenced lines total S-nitrosylation level in vivo at low temperature. Furthermore, BrMDHAR, BrAAO, and BrAPX gene transcript levels were dramatically up-regulated by BR, which in turn reduced the H2O2 content in the silenced lines. These findings demonstrated that the S-nitrosylation of MDHAR was essential to the improvement of BR on low-temperature tolerance in the mini Chinese cabbage.

13.
Angew Chem Int Ed Engl ; : e202415216, 2024 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-39370547

RESUMEN

The development of advanced bifunctional catalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is significant for rechargeable zinc-air batteries (ZABs). Herein, a unique dual active center alloying strategy is proposed to achieve the efficient bifunctional oxygen catalysis, and the high entropy effect is further exploited to modulate the structure and performance of the catalysts. The MOF-assisted pyrolysis-replacement-alloying method was employed to construct the CoCuFeAgRu high-entropy alloy (HEA), which are uniformly anchored in porous nitrogen-doped carbon nanosheets. Notably, the obtained HEA catalyst exhibits excellent catalytic performance for both ORR and OER, and a peak power density of 136. 53 mW cm-2 and an energy density of 987.9 mAh gZn-1, surpassing the most of the previously reported bifunctional oxygen electrocatalysts. Moreover, the assembled flexible rechargeable ZAB enables excellent performance even at the ultralow temperature of -40°C, with an energy density of 601.6 mAh gZn-1 and remarkable cycling stability up to 1,650 hours. Combined experimental and theoretical calculation results reveal that the excellent bifunctional catalytic activity of the HEA catalyst originated from the synergistic effect of the Ag and Ru dual active centers, and the optimization of the electronic structure by alloying effect.

14.
Gen Comp Endocrinol ; : 114617, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39368755

RESUMEN

The ricefield eel (Monopterus albus) is inherently timid and highly sensitive to stress. Our previous studies have shown that low-temperature weather could significantly affect the sperm vitality of ricefield eels. This study aims to investigate the regulatory mechanism of low-temperature effects on testicular function and sperm vitality in ricefield eels. The ricefield eels were initially reared at low (10 °C) and normal (25 °C) temperatures for 24 h. Low temperatures were found to induce the expression of pituitary pro-opiomelanocortin (POMC) and testes insulin-like growth factor-binding protein 1 (IGFBP1) mRNA expression, suggesting that the reduction in sperm vitality could be attributed to the activation of the stress axis. Moreover, the results indicated a significant decrease in sperm occupancy and count in the testes, along with a reduced percentage of motile sperm. Subsequent transcriptome analysis showed substantial inhibition of reproductive hormone genes (gnrh1, lh, and fsh) in the brain and pituitary, and downregulation of meiosis-related genes (dmc1, rec8, and sycp3) in the testes. These findings suggest that low temperatures might disrupt testicular development and spermatogenesis by inhibiting the reproductive axis. Metabolomics analysis then demonstrated a significant reduction in the levels of metabolites related to glycolysis, fatty acid metabolism, and the tricarboxylic acid (TCA) cycle in the testes after low-temperature treatment. Interestingly, the expression of zona pellucida sperm-binding proteins 3 and 4 (ZP3 and ZP4), which may affect sperm vitality and spermatogenesis, was significantly induced by low temperatures in the testes. In conclusion, these findings suggested that low temperatures might affect testicular function and sperm vitality by simultaneously activating the stress axis and inhibiting the reproductive axis and energy metabolism in the testes.

15.
J Hosp Infect ; 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39357541

RESUMEN

Validation of prion inactivation processes for medical devices relies on in vivo experimental protocols. However, bioassays are costly, long (one to two years) and ethically disputable. Additionally, results obtained with one prion strain, for example 263K (hamster-adapted strain originating from sheep scrapie), cannot be easily extrapolated to relevant human prion strains, further questioning the utility of bioassays. Over the past two decades, cell-free prion amplification assays have emerged as potential alternatives to bioassays. Rather than measuring prion infectivity, they quantify prion seeding activity, i.e. the capacity to convert the normal prion protein into the disease-associated isoform. The results obtained by an optimized cell-free assay termed miniaturized-bead protein misfolding cyclic amplification (mb-PMCA), with four processes using three different prion strains, 263K and two human prions derived from variant and sporadic Creutzfeldt-Jakob diseases, were compared to published bioassays using the same three strains and processes, when available. Tests performed on reference processes (steam, sodium hydroxide, sodium hypochlorite) and low temperature H2O2 sterilization process (STERRAD NXTM Advanced cycle), showed perfect alignment between mb-PMCA and available bioassays. STERRAD NXTM Advanced cycle was efficacious on all three prion strains. These data confirm that PMCA and in particular mb-PMCA is a relevant alternative to animal bioassays for assessment of prion inactivation processes and the interest of some low temperature H2O2 sterilization cycles.

16.
Artículo en Inglés | MEDLINE | ID: mdl-39260617

RESUMEN

Low-temperature stress poses a significant risk to the survival of both cultivated and wild fish populations. Existing studies have found that the pre-acclimation of fishes to moderate cold stress can stimulate the activation of acclimation pathways, thereby enhancing their tolerance to cold stress. The fitness of fish relies heavily on appropriately controlled transcriptional reactions to environmental changes. Despite previous characterization of gene expression profiles in various fish species during cold acclimation, the specific genes responsible for essential functions in this process remain largely unknown, particularly the down-regulated genes induced by cold acclimation. To investigate the genes involved in cold acclimation, this study employed real-time quantitative PCR (RT-qPCR), molecular cloning, microinjection techniques, and cold stress experiments to determine the genes that play an essential part in cold acclimation. Consequently, 18 genes were discovered to be down-regulated in larval zebrafish experiencing cold stress. All 18 genes successfully detected overexpression in zebrafish at 96 and 126 hpf (fold change ≥3), which declined with the growth of zebrafish. Following microinjection, it was observed that her8a, cyp51, lss, txnipb, and bhlha9 had an adverse impact on the survival rate of zebrafish larvae under cold stress. These genes have been identified to play significant roles in various biological processes. For instance, bhlha9 has been found to be involved in both limb development and temperature sensing and her8a has been implicated in neural development. Additionally, cyp51 and lss have been identified as participants in the cholesterol synthesis pathway. Txnipb has been reported to induce cell apoptosis, thereby potentially influencing the survival rate of zebrafish larvae under cold stress. These findings offered crucial data for the analysis of molecular processes related to cold tolerance and the development of cold-resistant fish breeding.


Asunto(s)
Respuesta al Choque por Frío , Regulación hacia Abajo , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/fisiología , Respuesta al Choque por Frío/genética , Clonación Molecular , Frío , Aclimatación/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Larva/genética , Larva/fisiología , Estrés Fisiológico/genética
17.
Molecules ; 29(18)2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39339501

RESUMEN

Selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3-SCR) has been implemented in response to the regulation of NOx emissions from stationary and mobile sources above 300 °C. However, the development of NH3-SCR catalysts active at low temperatures below 200 °C is still needed to improve the energy efficiency and to cope with various fuels. In this review article, recent reports on low-temperature NH3-SCR catalysts are systematically summarized. The redox property as well as the surface acidity are two main factors that affect the catalytic activity. The strong redox property is beneficial for the low-temperature NH3-SCR activity but is responsible for N2O formation. The multiple electron transfer system is more plausible for controlling redox properties. H2O and SOx, which are often found with NOx in flue gas, have a detrimental effect on NH3-SCR activity, especially at low temperatures. The competitive adsorption of H2O can be minimized by enhancing the hydrophobic property of the catalyst. Various strategies to improve the resistance to SOx poisoning are also discussed.

18.
Scand J Clin Lab Invest ; : 1-5, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263928

RESUMEN

Frozen saliva samples are often used for later determination of salivary glucocorticoids in research studies on stress and endocrine disorders. We studied the stability of cortisol and cortisone in saliva after six years of storage at -80 °C by repeated analysis of 153 stored aliquots, collected with Salivette®, using liquid chromatography tandem mass spectrometry. We found a very high agreement between the first and the repeated measurement after six years at -80 °C, for both cortisol and cortisone concentrations (rs= 0.96 and rs= 0.98, respectively). Passing-Bablok regression equations were y = 0.02 + 1.00x and y = 0.02 + 1.14x for cortisol and cortisone, respectively. We conclude that salivary cortisol and cortisone concentrations remain essentially unaltered after six years of storage at -80 °C.

19.
Int J Mol Sci ; 25(17)2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39273704

RESUMEN

Rapeseed is an important oil crop in the world. Wood vinegar could increase the yield and abiotic resistance of rapeseed. However, little is known about the underlying mechanisms of wood vinegar or its valid chemical components on rapeseed. In the present study, wood vinegar and butyrolactone (γ-Butyrolactone, one of the main components of wood vinegar) were applied to rapeseed at the seedling stage, and the molecular mechanisms of wood vinegar that affect rapeseed were studied by combining transcriptome and metabolomic analyses. The results show that applying wood vinegar and butyrolactone increases the biomass of rapeseed by increasing the leaf area and the number of pods per plant, and enhances the tolerance of rapeseed under low temperature by reducing membrane lipid oxidation and improving the content of chlorophyll, proline, soluble sugar, and antioxidant enzymes. Compared to the control, 681 and 700 differentially expressed genes were in the transcriptional group treated with wood vinegar and butyrolactone, respectively, and 76 and 90 differentially expressed metabolites were in the metabolic group. The combination of transcriptome and metabolomic analyses revealed the key gene-metabolic networks related to various pathways. Our research shows that after wood vinegar and butyrolactone treatment, the amino acid biosynthesis pathway of rapeseed may be involved in mediating the increase in rapeseed biomass, the proline metabolism pathway of wood vinegar treatment may be involved in mediating rapeseed's resistance to low-temperature stress, and the sphingolipid metabolism pathway of butyrolactone treatment may be involved in mediating rapeseed's resistance to low-temperature stress. It is suggested that the use of wood vinegar or butyrolactone are new approaches to increasing rapeseed yield and low-temperature resistance.


Asunto(s)
4-Butirolactona , Regulación de la Expresión Génica de las Plantas , Metabolómica , Transcriptoma , Metabolómica/métodos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacología , Transcriptoma/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ácido Acético , Frío , Brassica napus/crecimiento & desarrollo , Brassica napus/efectos de los fármacos , Brassica napus/genética , Brassica napus/metabolismo , Respuesta al Choque por Frío/efectos de los fármacos , Perfilación de la Expresión Génica , Madera/química , Madera/efectos de los fármacos , Metaboloma/efectos de los fármacos , Brassica rapa/crecimiento & desarrollo , Brassica rapa/efectos de los fármacos , Brassica rapa/metabolismo , Brassica rapa/genética
20.
Materials (Basel) ; 17(17)2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39274762

RESUMEN

Sn-Bi-based, low-temperature solder alloys are being developed to offer the electronics manufacturing industry a path to lower temperature processes. A critical challenge is the significant microstructural and lattice parameter changes that these alloys undergo at typical service temperatures, largely due to the variable solubility of Bi during the Sn phase. The influence of alloying additions in improving the performance of these alloys is the subject of much research. This study aims to enhance the understanding of how alloying with In influences these properties, which are crucial for improving the alloy's reliability. Using in situ heating synchrotron powder X-ray diffraction (PXRD), we investigated the Sn-57 wt% Bi-xIn (x = 0, 0.2, 0.5, 1, 3 wt%) alloys during heating and cooling. Our findings reveal that In modifies the microstructure, promoting more homogeneous Bi distribution during thermal cycling. This study not only provides new insights into the dissolution and precipitation behaviour of Bi in Sn-Bi-based alloys, but also demonstrates the potential of In to improve the thermal stability of these alloys. These innovations contribute significantly to advancing the performance and reliability of Sn-Bi-based, low-temperature solder alloys.

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