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1.
Front Physiol ; 15: 1464123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39364000

RESUMO

Temperature changes had a huge impact on the growth of aquaculture organisms, which mainly involved two parameters: the changing amplitude and the changing speed. Wide-adaptability and narrow-adaptability were divided by the amplitude, while fast-adaptability and slow-adaptability proposed in this article were divided based on the speed. Investigating the impact of the changing speed on artificial farming was vital. In this study, two fish species of wide-adaptability, Hippocampus kuda and Oryzias melatigma, were selected as research objects, explored the effects of temperature changing speeds on them under 2 changing amplitudes of 2°C and 4°C. The similarities and differences in their responses to temperature changes were analyzed and compared from the aspects of feeding, metabolism, physiology, immunity, and growth. The results showed that all 3 changing speeds (0.5°C/h, 1°C/h, and direct input) had no effect on the growth of O. melatigma under the 2°C amplitude, while there were significant differences in various aspects of H. kuda in the treatments with the speeds between 0.5°C/h and direct input, such as a significant difference in growth, in food intake, and in response speeds and response levels of several enzymes and related genes. Under 4°C amplitude, the impact of all 4 changing speeds (0.5°C/h, 1°C/h, 2°C/h and direct input) on both fish was more pronounced. H. kuda showed a significant difference of growth among 3 groups, and the critical safe speed was about 0.5°C/h in its heating treatments. And the growth decrease only occured the heating treatment of direct input in O. melatigma. Furthermore, some genes responded quickly and efficiently to the low-speed changes of temperature in H. kuda, but were inhibited in the treatments with high-speed changes. However, they can still express rapidly and efficiently in the high-speed treatments of O. melatigma, included several stress-related genes, lipid metabolic-related genes, and immune-related genes. Seen from these differences, the energy source used in H. kuda to resist stress was single and short-lived. So, under a long-term stress, H. kuda gradually transformed from normal physiological stress into pathological stress, leading to the outbreak of diseases. Therefore, for precise aquaculture of H. kuda, stricter and more precise control of environmental temperature is necessary to prevent rapid and big temperature changes from affecting the growth and survival of the seahorse.

2.
Int J Legal Med ; 138(5): 1991-2002, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38772947

RESUMO

In forensic casework, time since death (TSD) estimations may play a crucial role to establish chains of events as well as for alibi assessment in homicide cases. Classical TSD estimation relies on reasonably stable ambient temperatures and a correct documentation of ambient and rectal temperatures. This constancy is in some cases disturbed by post-discovery alterations of the crime scene, e.g. opening a window. In order to develop a better understanding of this alteration-based detrimental impact on TSD estimation as well as to identify feasible recommendations for casework, the present pilot study examined ambient temperature effects of different window opening scenarios regarding various time intervals (5 to 360 min) in a furnished 10 m2 apartment during winter. In this context, in addition to the ambient temperature and thus the cooling rate of the room, re-approximation to initial room temperature, potential influences on a nomogram-based time since death estimation using a fictitious case, and the impact of the measurement height above the ground were investigated. Our data indicate a significant reduction of the mean temperature decrease rate after 15 min regardless of the remaining opening time and a correlation with the size of the respective opening surfaces. Re-approximation to initial room temperatures was observed with up to three times longer than the initial opening time. There was no evidence of a substantial advantage of temperature measurements above the level of the corpse (> 0.1 m). The limitations of the study and its applicability for forensic casework are critically reviewed.


Assuntos
Mudanças Depois da Morte , Temperatura , Humanos , Projetos Piloto , Fatores de Tempo , Medicina Legal , Temperatura Corporal
3.
J Dent ; 145: 104998, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38636650

RESUMO

OBJECTIVES: The study aimed to introduce a novel two-step optical fiber-based photo-activation of dental resin-based composites (RBCs) for reducing polymerization shrinkage stress (PSS). METHODS: Proposed protocol design - in the first step, two flexible plastic optical fibers connected to a dental light curing unit (LCU), were used as light guides inserted into the filling to initiate low-irradiance polymerization from within; in the second step, fibers were extracted and remaining voids were filled with RBC, followed by conventional high-irradiance curing to finalize polymerization. Three bulk-fill RBCs were tested (Beautifil-Bulk Restorative, Filtek Bulk-fill Posterior, Tetric PowerFill) using tooth cavity models. Three non-invasive examination techniques were employed: Digital Holographic Interferometry, Infrared Thermography, and Raman spectroscopy for monitoring model deformation, RBC temperature change, and degree of conversion (DC), respectively. A control group (for each examined RBC) underwent conventional photo-activation. RESULTS: The experimental protocol significantly reduced model deformation by 15 - 35 %, accompanied by an 18 - 54 % reduction in RBC temperature change, emphasizing the impact of thermal shrinkage on PSS. Real-time measurements of deformation and temperature provided indirect insights into reaction dynamics and illuminated potential mechanisms underlying PSS reduction. After a 24-hour dark-storage period, DC outcomes comparable to conventional curing were observed, affirming the clinical applicability of the method. CONCLUSIONS: Protocol involving the use of two 1.5 mm fibers in the first step (300 mW/cm2 x 10 s), followed by a second conventional curing step (1000 mW/cm2 x 10 s), is recommended to achieve the desired PSS reduction, while maintaining adequate DC and ensuring efficient clinical application. CLINICAL SIGNIFICANCE: Obtained PSS reduction offers promise in potentially improving the performance of composite restorations. Additionally, leveraging the flexibility of optical fibers improves light guide approach for restorations on posterior teeth. Meanwhile, implementation in clinical practice is easily achievable by coupling the fibers with commercial dental LCUs using the provided plastic adapter.


Assuntos
Resinas Compostas , Teste de Materiais , Fibras Ópticas , Polimerização , Resinas Compostas/química , Resinas Compostas/efeitos da radiação , Humanos , Lâmpadas de Polimerização Dentária , Materiais Dentários/química , Materiais Dentários/efeitos da radiação , Temperatura , Análise Espectral Raman , Cura Luminosa de Adesivos Dentários/métodos , Estresse Mecânico , Propriedades de Superfície
4.
Sci Rep ; 14(1): 7800, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565607

RESUMO

The change of temperature and weather parameters is a major concern affecting sustainable development and impacting various sectors, such as agriculture, tourism, and industry. Changing weather patterns and their impact on water resources are important climatic factors that society is facing. In Thailand, climatological features such as ambient temperature, relative humidity, and precipitation play a substantial role in affecting extreme weather events, which cause damage to the economy, agriculture, tourism, and livelihood of people. To investigate recent serious changes in annual trends of temperature, relative humidity, and precipitation in Thailand, this study used the Mann-Kendall (MK) test and innovative trend analysis (ITA) methods. The MK test showed that all six regions had an upward trend in temperature and humidity index (humidex, how hot the weather feels to the average person), while relative humidity and precipitation showed both upward and downward trends across different regions. The ITA method further confirmed the upward trend in temperature and humidex and showed that most data points fell above the 1:1 line. However, the upward trend in most variables was not significant at the 5% level. The southern and eastern regions showed a significant upward trend in relative humidity and humidex at a 5% level of significance according to the MK test. The output of this study can help in the understanding of weather variations and predict future situations and can be used for adaptation strategies.

6.
Sci Total Environ ; 927: 171959, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38537816

RESUMO

Browning of freshwaters, mainly caused by increased terrestrial organic carbon loading, has been widely studied during the last decades. However, there are still uncertainties regarding both the extent of browning in different aquatic ecosystems and the actual importance of different driving forces and mechanisms. To refine understanding of the extent and causes of browning and its temporal variation, we gathered a comprehensive dataset including 746 Finnish water quality monitoring stations representing various waterbody types: streams, rivers, lakes, and coastal waters. Monotonic trend analyses revealed that TOC concentrations increased in all waterbody types during the study period from 1990 to 2020, whereas non-linear trends indicated that upward trends in TOC concentrations have substantially decreased since the mid-2000s. However, despite the upward trends levelling off, non-linear analyses also indicated decreases in TOC concentrations at only a few stations. As a result, the TOC contents of the majority of Finnish waterbody types in 2020 were at a higher level than in 1990. To examine the driving forces of increasing TOC concentrations, we selected 100 riverine catchments and linked the detected trends to 24 different drivers, including both hydrometeorological and catchment characteristics. The increased TOC concentrations in surface waters could be connected to diverse human impacts: hydrometeorological variables impacted by climate change, decreased acidic deposition, and land use in terms of peatland drainage. The importance of increased temperatures was emphasized, and its role as a driver of increased leaching of organic carbon in the forthcoming years is expected to grow with climate change.

7.
Mar Environ Res ; 195: 106369, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38262135

RESUMO

Seawater temperature change is an important concern for seed production and pond culture of sea cucumbers. The present study found that tentacle activity frequency was significantly lower in sea cucumbers exposed to continuous and rapid temperature increases than that of those at ambient temperature. Feeding behavior directly determines food intake, and further affects physiology and growth efficiency of sea cucumbers. This means that the decline in feeding caused by continuous and rapid temperature increases needs to be addressed in sea cucumber aquaculture. However, a sudden temperature change of 5 °C had no significant effect on behaviors of sea cucumbers. This indicates that continuous temperature increases, rather than a sudden increase, result in behavioral impacts on sea cucumbers. Therefore, we recommend aqua-farmers reduce the feeding amount for sea cucumbers during continuous and rapid temperature increases. In the present study, feeding behavior was significantly higher in sea cucumbers fed with 3% dietary tryptophan than that of those fed with 0% and 5% dietary tryptophan. This indicates that 3% dietary tryptophan increases the food intake of sea cucumbers, and mitigates the feeding decline caused by continuous and rapid temperature increase. This indicates that tryptophan has the potential to promote the feeding of sea cucumbers in seed production and pond culture. Adhesion capacity of sea cucumbers fed with 5% dietary tryptophan was significantly higher than that of individuals fed with 0% and 3% dietary tryptophan. This suggests that dietary tryptophan increases the feeding of sea cucumbers exposed to continuous and rapid temperature increases in pond culture and seed production. In addition, this study found that sea cucumbers fed with 3% dietary tryptophan had higher intestinal colony richness under the continuously rapid temperature change. The present study provides an effective method to improve adhesion behavior and to alleviate the impacts on feeding behavior for seed production and pond culture of sea cucumbers exposed to continuous and rapid temperature increases.


Assuntos
Pepinos-do-Mar , Stichopus , Humanos , Animais , Stichopus/fisiologia , Suplementos Nutricionais/análise , Triptofano , Temperatura , Imunidade Inata , Água do Mar
8.
J Sci Food Agric ; 104(6): 3228-3234, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38072810

RESUMO

BACKGROUND: Bacillus amyloliquefaciens has excellent protease production ability and holds great prospects for application in the solid-state fermentation of soybean meal (SBM). RESULTS: Among eight strains of bacteria, Bacillus amyloliquefaciens subsp. plantarum CICC 10265, which exhibited higher protease production, was selected as the fermentation strain. The protease activity secreted by this strain reached 106.41 U mL-1 . The microbial community structure differed significantly between natural fermentation and inoculation-enhanced fermented soybean meal (FSBM), with the latter showing greater stability and inhibition of miscellaneous bacterial growth. During fermentation, the temperature inside the soybean meal increased, and the optimal environmental temperature for FSBM was found to be between 35 and 40 °C. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and nitrogen solubility index (NSI) results demonstrated that solid-state fermentation had a degrading effect on highly denatured proteins in SBM, resulting in an NSI of 67.1%. CONCLUSION: Bacillus amyloliquefaciens subsp. plantarum CICC 10265 can enhance the NSI of SBM in solid-state fermentation and inhibit the growth of miscellaneous bacteria. © 2023 Society of Chemical Industry.


Assuntos
Anti-Infecciosos , Bacillus , Temperatura Alta , Fermentação , Farinha , Solubilidade , Glycine max , Bactérias/metabolismo , Peptídeo Hidrolases/metabolismo , Nitrogênio
9.
Environ Res ; 242: 117778, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036207

RESUMO

The continuous performance and denitrification characteristics of carriers were investigated in two modified enhanced ecological floating beds (EFBs), one with only ceramsite and the other with ceramsite and extra additional stereo-elastic packing. Over a period of more than 414 days, the extra carrier was found to improve nitrogen removal while enhancing the system's resistance to seasonal temperature variations. The denitrification of all carriers in EFBs was inhibited in practice by seasonal temperature change, especially temperature rose from below 20 °C to above 20 °C and the inhibition rate of nitrous nitrogen (NO2--N) reduction was consistently above 91%, which was higher than that of nitrate nitrogen (NO3--N). However, the denitrification process including the rate and the resistance to temperature changes of ceramsite in the same EFBs with stereo-elastic packing at different temperatures, was consistently improved. The removal rate of NO3--N and NO2--N increased by up to 23.5% and 19.5%, respectively. The potential denitrification rates of all carriers increased with time which was also evidenced by in PICRUSt results, which showed that the abundances of predicted functional genes encoding NO3--N and NO2--N reductase increased over time. The dominant denitrifier also differed over time due to seasonal temperature changes.


Assuntos
Poluição Difusa , Purificação da Água , Temperatura , Dióxido de Nitrogênio , Estações do Ano , Nitratos , Nitrogênio , Reatores Biológicos
10.
Front Public Health ; 11: 1322019, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38131020

RESUMO

Background: With the intensification of global climate warming, extreme low temperature events such as cold spells have become an increasingly significant threat to public health. Few studies have examined the relationship between cold spells and mortality in multiple Chinese provinces. Methods: We employed health impact functions for temperature and mortality to quantify the health risks of the first winter cold spell in China on November 26th, 2022, and analyzed the reasons for the stronger development of the cold spell in terms of the circulation field. Results: This cold spell was a result of the continuous reinforcement of the blocking high-pressure system in the Ural Mountains, leading to the deepening of the cold vortex in front of it. Temperature changes associated with the movement of cold fronts produced additional mortality risks and mortality burdens. In general, the average excess risk (ER) of death during the cold spell in China was 2.75%, with a total cumulative excess of 369,056 deaths. The health risks associated with temperatures were unevenly distributed spatially in China, with the ER values ranging from a minimum of 0.14% to a maximum of 5.72%, and temperature drops disproportionately affect southern regions of China more than northern regions. The cumulative excess deaths exibited the highest in eastern and central China, with 87,655 and 80,230 respectively, and the lowest in northwest China with 27,474 deaths. Among the provinces, excess deaths pronounced the highest in Shandong with 29,492 and the lowest in Tibet with only 196. Conclusion: The study can provide some insight into the mortality burden of cold spells in China, while emphasising the importance of understanding the complex relationship between extreme low temperature events and human health. The outcomes could provide valuable revelations for informing pertinent public health policies.


Assuntos
Clima , Temperatura Baixa , Humanos , Temperatura , Estações do Ano , China/epidemiologia
11.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834085

RESUMO

Temperature sensation involves thermosensitive TRP (thermoTRP) and non-TRP channels. Drosophila larval Class III (CIII) neurons serve as the primary cold nociceptors and express a suite of thermoTRP channels implicated in noxious cold sensation. How CIII neurons code temperature remains unclear. We combined computational and electrophysiological methods to address this question. In electrophysiological experiments, we identified two basic cold-evoked patterns of CIII neurons: bursting and spiking. In response to a fast temperature drop to noxious cold, CIII neurons distinctly mark different phases of the stimulus. Bursts frequently occurred along with the fast temperature drop, forming a peak in the spiking rate and likely coding the high rate of the temperature change. Single spikes dominated at a steady temperature and exhibited frequency adaptation following the peak. When temperature decreased slowly to the same value, mainly spiking activity was observed, with bursts occurring sporadically throughout the stimulation. The spike and the burst frequencies positively correlated with the rate of the temperature drop. Using a computational model, we explain the distinction in the occurrence of the two CIII cold-evoked patterns bursting and spiking using the dynamics of a thermoTRP current. A two-parameter activity map (Temperature, constant TRP current conductance) marks parameters that support silent, spiking, and bursting regimes. Projecting on the map the instantaneous TRP conductance, governed by activation and inactivation processes, reflects temperature coding responses as a path across silent, spiking, or bursting domains on the map. The map sheds light on how various parameter sets for TRP kinetics represent various types of cold-evoked responses. Together, our results indicate that bursting detects the high rate of temperature change, whereas tonic spiking could reflect both the rate of change and magnitude of steady cold temperature.


Assuntos
Temperatura Baixa , Drosophila , Animais , Larva , Temperatura , Células Receptoras Sensoriais/fisiologia , Potenciais de Ação/fisiologia
12.
Dent Mater J ; 42(6): 894-900, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37766575

RESUMO

This study investigated the effect of translucency and absorbance of conventional (FiltekTM-Z350-XT) and bulk-fill (Tetric®-N-Ceram) composites on temperature change during photopolymerization, using a non-contact infrared sensor. Three shades from each composite were selected to prepare disk-shaped specimens (n=3), which then photopolymerized with LED-light for 20 s. A second light exposure was performed on the photopolymerized specimens. The first peak temperature rise during composite photopolymerization (ΔTtotal), second peak temperature rise by the light (ΔTlight), and net peak temperature rise by composite curing heat (ΔTcomposite) were obtained from the temperature change vs. time curve. The changes in ΔTtotal and ΔTlight with varying the composite shade were greater than those in ΔTcomposite. The conventional composite showed higher ΔTtotal and ΔTlight than bulk-fill composite. ΔTtotal and ΔTlight increased as translucency parameter decreased, and absorbance increased. The potential risk for heat-induced pulpal damage should be considered when selecting a composite shade, especially for deep cavities.


Assuntos
Resinas Compostas , Temperatura Alta , Temperatura , Teste de Materiais
13.
Environ Sci Pollut Res Int ; 30(45): 101053-101063, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37644268

RESUMO

With the deepening of research on the correlation between meteorological factors and autoimmune diseases, the relationship between climate change and dermatomyositis (DM) has come to our attention. This study aimed to explore the short-term correlation between meteorological factors and DM outpatient visits. Daily records of hospital outpatient visits for DM, air pollutants, and meteorological factor data in Hefei from January 1, 2018 to December 31, 2021 were obtained. The mean temperature (MT), relative humidity (RH), diurnal temperature range (DTR), and temperature change between neighboring days (TCN) were used to quantify environmental temperature and humidity and their variations. And we performed a time series analysis using a generalized linear model (GLM) in combination with a distributed lag nonlinear model (DLNM). Furthermore, gender and age were further stratified for the analysis. The sensitivity analysis was also performed. A total of 4028 DM outpatient visits were recorded during this period. There were statistically significant associations of low temperature (5th, 1.5 °C), low RH (1st, 48.6%), high RH (99th, 99%), high DTR (75th, 12.6°c), and low TCN (10th, -2.7 °C) that were associated with risk of DM outpatient visits, with lag days of 30, 16, 16, 10, and 14, respectively. Moreover, women were more susceptible to high RH exposure and low TCN exposure, while the elderly were more susceptible to low temperature. This study concluded that exposure to low temperature, extreme RH, and temperature changes (especially high DTR and low TCN) was associated with an increased risk of DM outpatient visits.


Assuntos
Dermatomiosite , Pacientes Ambulatoriais , Humanos , Feminino , Idoso , Mudança Climática , Dermatomiosite/epidemiologia , Temperatura , China , Febre
14.
J Oral Implantol ; 49(4): 401-406, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527174

RESUMO

This study aimed to evaluate temperature changes in titanium and ceramic implants after using a 445-nm diode laser under different in vitro conditions. Titanium (Ti) and ceramic (Zr) dental implants were placed into a bone analog, and an intrabony defect was created at each implant. A 445-nm diode laser was used to irradiate the defects for 30 seconds, noncontact, at 2 W in continuous wave (c.w.) and pulsed mode. The experiment was done at room temperature (21.0 ± 1°C) and in a water bath (37.0 ± 1°C). Two thermocouple probes were used to record real-time temperature changes (°C) at the coronal part of the implant (Tc) and the apex (Ta). The temperature was recorded at time 0 (To) and after 30 seconds of irradiation (Tf). The average temperature change was calculated, and a descriptive analysis was conducted (P < .05). The Ti implant resulted in the highest ΔT values coronally (29.6°C) and apically (6.7°C) using continuous wave at 21°C. The Zr implant increased to 26.4°C coronally and 5.2°C apically. In the water bath, the coronal portion of the Ti and Zr implants rose to 14.2°C and 14.01°C, respectively, using continuous waves. The ΔT values for Ti were 11.9°C coronally and 1.7°C apically when placed in a water bath using pulsed mode. The lowest ΔT occurred on the Zr implant with ΔTc and ΔTa of 4.8°C and 0.78°C, respectively. Under in vitro conditions, the 445-nm diode laser in pulsed mode seems to be safe for use on ceramic implants and should be used with caution on titanium implants.


Assuntos
Implantes Dentários , Lasers Semicondutores , Titânio , Temperatura , Água
15.
Small ; 19(36): e2300333, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37150875

RESUMO

2D magnets can potentially revolutionize information technology, but their potential application to cooling technology and magnetocaloric effect (MCE) in a material down to the monolayer limit remain unexplored. Herein, it is revealed through multiscale calculations the existence of giant MCE and its strain tunability in monolayer magnets such as CrX3 (X = F, Cl, Br, I), CrAX (A = O, S, Se; X = F, Cl, Br, I), and Fe3 GeTe2 . The maximum adiabatic temperature change ( Δ T ad max $\Delta T_{{\rm{ad}}}^{\max }$ ), maximum isothermal magnetic entropy change, and specific cooling power in monolayer CrF3 are found as high as 11 K, 35 µJ m-2  K-1 , and 3.5 nW cm-2 under a magnetic field of 5 T, respectively. A 2% biaxial and 5% a-axis uniaxial compressive strain can remarkably increase Δ T ad max $\Delta T_{{\rm{ad}}}^{\max }$ of CrCl3 and CrOF by 230% and 37% (up to 15.3 and 6.0 K), respectively. It is found that large net magnetic moment per unit area favors improved MCE. These findings advocate the giant-MCE monolayer magnets, opening new opportunities for magnetic cooling at nanoscale.

16.
Sci China Life Sci ; 66(8): 1800-1817, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36949229

RESUMO

The discovery of biological activities of natural products plays a vital part in drug development. The mechanism by which organisms respond to temperature changes via biosynthesis of natural products remained largely cryptic. A thermophilic fungus under cold stress turned black and accumulated a polyketide metabolite 1 and lipid mass. Deficiency in 1 caused melanin loss and accumulated extra lipid mass, unexpectedly leading to seriously damaged mitochondria diagnostic for ferroptosis. Further analysis revealed that lipid mass induced by cold stress intensively increased ferroptosis risk and 1 functioned as cell wall reinforcer against mass lipid accumulation and as reactive oxygen species scavenger against lipid peroxidation. We also found that melanin in mice lowered lipid level but enhanced animal resistance to cold stress. Treatment with melanin precursors significantly increased mouse cell survival rate under cold stress. Our results unveiled a metabolite-lipid-ferroptosis-cold relationship, which provided mechanistic insights into the functions of most common metabolites and into diseases related to cold stress. These findings opened a perspective for developing anti-cold and anti-ferroptosis therapeutics and agents.


Assuntos
Fungos , Melaninas , Camundongos , Animais , Temperatura , Espécies Reativas de Oxigênio/metabolismo , Fungos/metabolismo , Lipídeos
17.
ACS Appl Mater Interfaces ; 15(14): 18065-18073, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36996275

RESUMO

As an alternative to conventional vapor-compression refrigeration, cooling devices based on electrocaloric (EC) materials are environmentally friendly and highly efficient, which are promising in realizing solid-state cooling. Lead-free ferroelectric ceramics with competitive EC performance are urgently desirable for EC cooling devices. In the past few decades, constructing phase coexistence and high polarizability have been two crucial factors in optimizing the EC performance. Different from the external stress generated through heavy equipment and inner interface stress caused by complex interface structures, the internal lattice stress induced by ion substitution engineering is a relatively simple and efficient means to tune the phase structure and polarizability. In this work, we introduce low-radius Li+ into BaZr0.2Ti0.8O3 (BZT) to form a particular A-site substituted cell structure, leading to a change of the internal lattice stress. With the increase of lattice stress, the fraction of the rhombohedral phase in the rhombohedral-cubic (R-C) coexisting system and ferroelectricity are all pronouncedly enhanced for the Li2CO3-doped sample, resulting in the significant enhancement of saturated polarization (Ps) as well as EC performance [e.g., adiabatic temperature change (ΔT) and isothermal entropy change (ΔS)]. Under the same conditions (i.e., 333 K and 70 kV cm-1), the ΔT of 5.7 mol % Li2CO3-doped BZT is 1.37 K, which is larger than that of the pure BZT ceramics (0.61 K). Consequently, in cooperation with the great improvement of electric field breakdown strength (Eb) from 70 to 150 kV cm-1, 5.7 mol % Li2CO3-doped BZT achieved a large ΔT of 2.26 K at a temperature of 333 K, which is a competitive performance in the field of electrocaloric effect (ECE). This work provides a simple but effective approach to designing high-performance electrocaloric materials for next-generation refrigeration.

18.
Environ Sci Pollut Res Int ; 30(19): 56513-56521, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36920607

RESUMO

The prevalence of glaucoma has seasonal variation in population, but the role of ambient temperature and its variation remains unclear in this seasonal trend. So, we conducted a time-stratified case-crossover study to examine the association of ambient temperature and temperature change between neighboring days (TCN) with the risk of acute glaucoma. Data on meteorological parameters and glaucoma outpatient visit between 2015 and 2021 covered all districts of Shanghai. Conditional logistic regression with distributed lag nonlinear model was applied to estimate the association of temperature or TCN with the risk of acute glaucoma. A total of 7,746 patients diagnosed with acute primary angle-closure glaucoma (APACG) were included in this analysis. We observed a significant increase in the risk of acute glaucoma with cold temperature and temperature drop. Compared with the referent temperature (32℃), moderate low (12 °C) and extreme low (4 °C) temperature exposures were associated with higher risk of acute glaucoma outpatient visit, with the highest cumulative OR of 1.46 (95% CI: 1.11, 1.91) and 1.50 (95% CI: 1.09, 2.06) over lag 0-2 days. Temperature drop (TCN = - 4 °C) also increases the risk of acute glaucoma (OR = 1.34, 95% CI: 1.07, 1.67) over lag 0-7 days, comparing with no temperature change. Patients of female and above age 65 were more vulnerable to cold exposure and temperature drop. This case-crossover study provided novel and robust individual-level evidence that low ambient temperature and temperature drop significantly increase the acute glaucoma risk. The findings provide protective strategies for glaucoma patient, especially for female and the old, under cold exposure and sudden temperature decline.


Assuntos
Glaucoma de Ângulo Fechado , Glaucoma , Humanos , Feminino , Idoso , Temperatura Baixa , Estudos Cross-Over , China/epidemiologia , Fatores de Risco , Estações do Ano , Glaucoma/epidemiologia , Doença Aguda , Temperatura Alta
19.
Sensors (Basel) ; 23(4)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36850352

RESUMO

The remote sensing imaging requirements of aerial cameras require their optical system to have wide temperature adaptability. Based on the optical passive athermal technology, the expression of thermal power offset of a single lens in the catadioptric optical system is first derived, and then a mathematical model for efficient optimization of materials is established; finally, the mechanical material combination (mirror and housing material) is optimized according to the comprehensive weight of offset with temperature change and the position change of the equivalent single lens, and achieve optimization of the lens material on an athermal map. In order to verify the effectiveness of the method, an example of a catadioptric aerial optical system with a focal length of 350 mm is designed. The results show that in the temperature range of -40 °C to 60 °C, the diffraction-limited MTF of the designed optical system is 0.59 (at 68 lp/mm), the MTF of each field of view is greater than 0.39, and the thermal defocus is less than 0.004 mm, which is within one time of the focal depth, indicating that the imaging quality of the optical system basically does not change with temperature, meeting the stringent application requirements of the aerial camera.

20.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835290

RESUMO

As sessile organisms, plants have evolved complex mechanisms to rapidly respond to ever-changing ambient temperatures. Temperature response in plants is modulated by a multilayer regulatory network, including transcriptional and post-transcriptional regulations. Alternative splicing (AS) is an essential post-transcriptional regulatory mechanism. Extensive studies have confirmed its key role in plant temperature response, from adjustment to diurnal and seasonal temperature changes to response to extreme temperatures, which has been well documented by previous reviews. As a key node in the temperature response regulatory network, AS can be modulated by various upstream regulations, such as chromatin modification, transcription rate, RNA binding proteins, RNA structure and RNA modifications. Meanwhile, a number of downstream mechanisms are affected by AS, such as nonsense-mediated mRNA decay (NMD) pathway, translation efficiency and production of different protein variants. In this review, we focus on the links between splicing regulation and other mechanisms in plant temperature response. Recent advances regarding how AS is regulated and the following consequences in gene functional modulation in plant temperature response will be discussed. Substantial evidence suggests that a multilayer regulatory network integrating AS in plant temperature response has been unveiled.


Assuntos
Processamento Alternativo , Plantas , Temperatura , Plantas/genética , Splicing de RNA , RNA , Regulação da Expressão Gênica de Plantas
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