Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122.265
Filtrar
1.
Environ Monit Assess ; 196(5): 410, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564063

RESUMO

A limited number of meteorological stations and sparse data challenge microclimate assessment in urban areas. Therefore, it is necessary to complement these data with additional measurements to achieve a denser spatial coverage, enabling a detailed representation of the city's microclimatic features. In this study, conducted in Zagreb, Croatia, mobile air temperature measurements were utilized and compared with satellite-derived land surface temperature (LST). Here, air temperature measurements were carried out using bicycles and an instrument with a GPS receiver and temperature probe during a heat wave in June 2021, capturing the spatial pattern of air temperature to highlight the city's microclimate characteristics (i.e. urban heat load; UHL) in extremely hot weather conditions. Simultaneously, remotely sensed LST was retrieved from the Landsat-8 satellite. Air temperature measurements were compared to city-specific street type classification, while neighbourhood heat load characteristics were analysed based on local climate zones (LCZ) and LST. Results indicated significant thermal differences between surface types and urban forms and between street types and LCZs. Air temperatures reached up to 35 °C, while LST exceeded 40 °C. City parks, tree-lined streets and areas near blue infrastructure were 1.5-3 °C cooler than densely built areas. Temperature contrasts between LCZs in terms of median LST were more emphasised and reached 9 °C between some classes. These findings highlight the importance of preserving green areas to reduce UHL and enhance urban resilience. Here, exemplified by the city of Zagreb, it has been demonstrated that the use of multiple datasets allows a comprehensive understanding of temperature patterns and their implications for urban climate research.


Assuntos
Temperatura Alta , Imagens de Satélites , Croácia , Monitoramento Ambiental , Temperatura
3.
Sci Rep ; 14(1): 8237, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589450

RESUMO

Coffee professionals have long known that the "roast profile," i.e., the temperature versus time inside the roaster, strongly affects the flavor and quality of the coffee. A particularly important attribute of brewed coffee is the perceived sourness, which is known to be strongly correlated to the total titratable acidity (TA). Most prior work has focused on laboratory-scale roasters with little control over the roast profile, so the relationship between roast profile in a commercial-scale roaster and the corresponding development of TA to date remains unclear. Here we investigate roast profiles of the same total duration but very different dynamics inside a 5-kg commercial drum roaster, and we show that the TA invariably peaks during first crack and then decays to its original value by second crack. Although the dynamics of the TA development varied with roast profile, the peak TA surprisingly exhibited almost no statistically significant differences among roast profiles. Our results provide insight on how to manipulate and achieve desired sourness during roasting.


Assuntos
Coffea , Temperatura Alta , Temperatura , Tempo
4.
Environ Sci Technol ; 58(14): 6226-6235, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557021

RESUMO

The updated climate models provide projections at a fine scale, allowing us to estimate health risks due to future warming after accounting for spatial heterogeneity. Here, we utilized an ensemble of high-resolution (25 km) climate simulations and nationwide mortality data from 306 Chinese cities to estimate death anomalies attributable to future warming. Historical estimation (1986-2014) reveals that about 15.5% [95% empirical confidence interval (eCI):13.1%, 17.6%] of deaths are attributable to nonoptimal temperature, of which heat and cold corresponded to attributable fractions of 4.1% (eCI:2.4%, 5.5%) and 11.4% (eCI:10.7%, 12.1%), respectively. Under three climate scenarios (SSP126, SSP245, and SSP585), the national average temperature was projected to increase by 1.45, 2.57, and 4.98 °C by the 2090s, respectively. The corresponding mortality fractions attributable to heat would be 6.5% (eCI:5.2%, 7.7%), 7.9% (eCI:6.3%, 9.4%), and 11.4% (eCI:9.2%, 13.3%). More than half of the attributable deaths due to future warming would occur in north China and cardiovascular mortality would increase more drastically than respiratory mortality. Our study shows that the increased heat-attributable mortality burden would outweigh the decreased cold-attributable burden even under a moderate climate change scenario across China. The results are helpful for national or local policymakers to better address the challenges of future warming.


Assuntos
Temperatura Baixa , Temperatura Alta , Temperatura , Cidades , China/epidemiologia , Mudança Climática , Mortalidade
5.
J Neural Eng ; 21(2)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38565132

RESUMO

Objective.Understanding the intricate relationship between structural connectivity (SC) and functional connectivity (FC) is pivotal for understanding the complexities of the human brain. To explore this relationship, the heat diffusion model (HDM) was utilized to predict FC from SC. However, previous studies using the HDM have typically predicted FC at a critical time scale in the heat kernel equation, overlooking the dynamic nature of the diffusion process and providing an incomplete representation of the predicted FC.Approach.In this study, we propose an alternative approach based on the HDM. First, we introduced a multiple-timescale fusion method to capture the dynamic features of the diffusion process. Additionally, to enhance the smoothness of the predicted FC values, we employed the Wavelet reconstruction method to maintain local consistency and remove noise. Moreover, to provide a more accurate representation of the relationship between SC and FC, we calculated the linear transformation between the smoothed FC and the empirical FC.Main results.We conducted extensive experiments in two independent datasets. By fusing different time scales in the diffusion process for predicting FC, the proposed method demonstrated higher predictive correlation compared with method considering only critical time points (Singlescale). Furthermore, compared with other existing methods, the proposed method achieved the highest predictive correlations of 0.6939±0.0079 and 0.7302±0.0117 on the two datasets respectively. We observed that the visual network at the network level and the parietal lobe at the lobe level exhibited the highest predictive correlations, indicating that the functional activity in these regions may be closely related to the direct diffusion of information between brain regions.Significance.The multiple-timescale fusion method proposed in this study provides insights into the dynamic aspects of the diffusion process, contributing to a deeper understanding of how brain structure gives rise to brain function.


Assuntos
Conectoma , Humanos , Conectoma/métodos , Temperatura Alta , Encéfalo , Imagem de Tensor de Difusão/métodos , Lobo Parietal , Imageamento por Ressonância Magnética/métodos
6.
BMC Cancer ; 24(1): 437, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594603

RESUMO

BACKGROUND: Soft tissue sarcomas (STS), have significant inter- and intra-tumoral heterogeneity, with poor response to standard neoadjuvant radiotherapy (RT). Achieving a favorable pathologic response (FPR ≥ 95%) from RT is associated with improved patient outcome. Genomic adjusted radiation dose (GARD), a radiation-specific metric that quantifies the expected RT treatment effect as a function of tumor dose and genomics, proposed that STS is significantly underdosed. STS have significant radiomic heterogeneity, where radiomic habitats can delineate regions of intra-tumoral hypoxia and radioresistance. We designed a novel clinical trial, Habitat Escalated Adaptive Therapy (HEAT), utilizing radiomic habitats to identify areas of radioresistance within the tumor and targeting them with GARD-optimized doses, to improve FPR in high-grade STS. METHODS: Phase 2 non-randomized single-arm clinical trial includes non-metastatic, resectable high-grade STS patients. Pre-treatment multiparametric MRIs (mpMRI) delineate three distinct intra-tumoral habitats based on apparent diffusion coefficient (ADC) and dynamic contrast enhanced (DCE) sequences. GARD estimates that simultaneous integrated boost (SIB) doses of 70 and 60 Gy in 25 fractions to the highest and intermediate radioresistant habitats, while the remaining volume receives standard 50 Gy, would lead to a > 3 fold FPR increase to 24%. Pre-treatment CT guided biopsies of each habitat along with clip placement will be performed for pathologic evaluation, future genomic studies, and response assessment. An mpMRI taken between weeks two and three of treatment will be used for biological plan adaptation to account for tumor response, in addition to an mpMRI after the completion of radiotherapy in addition to pathologic response, toxicity, radiomic response, disease control, and survival will be evaluated as secondary endpoints. Furthermore, liquid biopsy will be performed with mpMRI for future ancillary studies. DISCUSSION: This is the first clinical trial to test a novel genomic-based RT dose optimization (GARD) and to utilize radiomic habitats to identify and target radioresistance regions, as a strategy to improve the outcome of RT-treated STS patients. Its success could usher in a new phase in radiation oncology, integrating genomic and radiomic insights into clinical practice and trial designs, and may reveal new radiomic and genomic biomarkers, refining personalized treatment strategies for STS. TRIAL REGISTRATION: NCT05301283. TRIAL STATUS: The trial started recruitment on March 17, 2022.


Assuntos
Temperatura Alta , Sarcoma , Humanos , 60570 , Sarcoma/diagnóstico por imagem , Sarcoma/genética , Sarcoma/radioterapia , Genômica , Doses de Radiação
7.
PLoS One ; 19(4): e0301719, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38640130

RESUMO

This work aims to investigate the analytical solution of a two-dimensional fuzzy fractional-ordered heat equation that includes an external diffusion source factor. We develop the Sawi homotopy perturbation transform scheme (SHPTS) by merging the Sawi transform and the homotopy perturbation scheme. The fractional derivatives are examined in Caputo sense. The novelty and innovation of this study originate from the fact that this technique has never been tested for two-dimensional fuzzy fractional ordered heat problems. We presented two distinguished examples to validate our scheme, and the solutions are in fuzzy form. We also exhibit contour and surface plots for the lower and upper bound solutions of two-dimensional fuzzy fractional-ordered heat problems. The results show that this approach works quite well for resolving fuzzy fractional situations.


Assuntos
Estro , Temperatura Alta , Animais , Difusão
8.
Carbohydr Polym ; 335: 122081, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616099

RESUMO

The study explored the plasma-activated water (PAW)-assisted heat-moisture treatment (HMT) on the structural, physico-chemical properties, and in vitro digestibility of extrusion-recrystallized starch. Native starch of hausa potatoes underwent modification through a dual process involving PAW-assisted HMT (PHMT) followed by extrusion-recrystallization (PERH) using a twin-screw extruder. The PHMT sample showed surface roughness and etching with a significantly greater (p ≤ 0.05) RC (20.12 %) and ΔH (5.86 J/g) compared to DHMT. In contrast, PERH-induced structural damage, resulting in an irregular block structure, and altered the crystalline pattern from A to B + V-type characterized by peaks at 17.04°, 19.74°, 22°, and 23.94°. DSC analysis showed two endothermic peaks in all the extrusion-recrystallized samples, having the initial peak attributed to the melting of structured amylopectin chains and the second one linked to the melting of complexes formed during retrogradation. Dual-modified samples displayed notably increased transition temperatures (To1 74.54 and 74.17 °C, To2 122.65 and 121.49 °C), along with increased RS content (43.76 %-45.30 %). This study envisages a novel approach for RS preparation and broadens the utilization of PAW in starch modification synergistically with environmentally friendly techniques.


Assuntos
Hipertermia Induzida , Solanum tuberosum , Temperatura Alta , Amido , Água
9.
Biochem Biophys Res Commun ; 709: 149725, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38579617

RESUMO

Proteinoids are synthetic polymers that have structural similarities to natural proteins, and their formation is achieved through the application of heat to amino acid combinations in a dehydrated environment. The thermal proteins, initially synthesised by Sidney Fox during the 1960s, has the ability to undergo self-assembly, resulting in the formation of microspheres that resemble cells. These microspheres have fascinating biomimetic characteristics. In recent studies, substantial advancements have been made in elucidating the electrical signalling phenomena shown by proteinoids, hence showcasing their promising prospects in the field of neuro-inspired computing. This study demonstrates the advancement of experimental prototypes that employ proteinoids in the construction of fundamental neural network structures. The article provides an overview of significant achievements in proteinoid systems, such as the demonstration of electrical excitability, emulation of synaptic functions, capabilities in pattern recognition, and adaptability of network structures. This study examines the similarities and differences between proteinoid networks and spontaneous neural computation. We examine the persistent challenges associated with deciphering the underlying mechanisms of emergent proteinoid-based intelligence. Additionally, we explore the potential for developing bio-inspired computing systems using synthetic thermal proteins in forthcoming times. The results of this study offer a theoretical foundation for the advancement of adaptive, self-assembling electronic systems that operate using artificial bio-neural principles.


Assuntos
Aminoácidos , Proteínas , Proteínas/metabolismo , Temperatura Alta , Redes Neurais de Computação
10.
Zhongguo Zhong Yao Za Zhi ; 49(3): 618-624, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621865

RESUMO

In the process of preparing presonalized concentrated watered pills, the decoction needs to be concentrated by heat and mixed with medicinal slices or powder to prepare a wet mass. However, some of the traditional Chinese medicine(TCM) components are easily decomposed or transformed by heat. In order to optimize the preparation process of presonalized TCM concentrated watered pills and reduce the loss of heat-unstable components in prescriptions, this study uses five compound TCM prescriptions containing heat-unstable components as model prescriptions, namely the Linggui Zhugan Formula, Xiaochengqi Formula, Sanpian Formula, Xiaoer Qixing Formula, and Xiaoyao Formula. Based on the two kinds of preparation process of presonalized concentrated watered pills previously established by our research group, whole extract concentrated watered pills and concentrated watered pills without excipients are prepared, respectively. Characteristic maps are measured and compared with those of the corresponding decoction. The results show that the characteristic maps of the concentrated watered pills without excipients of the five model prescriptions are very close to those of the decoction, and the number of characteristic peaks and peak areas are higher than those of whole extract concentrated watered pills. In addition, the peak area of some peaks is higher than that of the corresponding decoction. Thus, it is recommended to select the preparation process of prescription-based concentrated watered pills without excipients based on the "unification of medicines and excipients" to preserve those heat-unstable components more effectively when the prescription contains a heat-unstable component of TCM. This study provides a basis for the subsequent reasonable development and application of presonalized TCM pills.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Excipientes , Temperatura Alta , Prescrições
11.
Zhongguo Zhong Yao Za Zhi ; 49(4): 853-857, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621892

RESUMO

Gypsum Fibrosum, as a classic heat-clearing medicine, is widely used in the clinical practice of traditional Chinese medicine(TCM). However, debates exist about the material basis and mechanism of its efficacy. Therefore, this paper reviewed the recent research progress in the heat-clearing effect and mechanism of Gypsum Fibrosum and discussed the material basis for the heat-clearing effect of this medicine. Ca~(2+) may inhibit the upward movement of temperature set point by regulating the Na~+/Ca~(2+) level in the heat-regulating center. Moreover, trace elements may inhibit the rise of body temperature by regulating the immune system, promoting the absorption of Ca~(2+), and affecting the synthesis of prostaglandin E2(PGE2). This review aims to enrich the knowledge about the mechanism of Gypsum Fibrosum in clearing heat and provides a scientific basis for the clinical application and further development of Gypsum Fibrosum.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/farmacologia , Sulfato de Cálcio/farmacologia , Temperatura Alta , Medicina Tradicional Chinesa
12.
Artigo em Inglês | MEDLINE | ID: mdl-38574988

RESUMO

Different physiological performances are often optimized at slightly varying temperatures, which can lead to ectotherms selecting higher body temperatures during certain physiological efforts (e.g., digestion, reproduction). Such thermophilic responses can lead to temperature-based tradeoffs between two physiological activities with differing optimal temperatures or between optimizing a physiological activity and water balance, as water loss is elevated at higher temperatures. For example, ectotherms will often select a higher body temperature after consuming a meal, but the extent to which body temperature is elevated after eating is affected by its hydric state. Despite this known hydration state-based suppression of thermophily associated with digestion, the impact of this reduced body temperature on digestion performance is unknown. Accordingly, we determined whether small, thermophily-relevant changes in body temperature impact digestive efficiency or passage time and whether sex influenced the extent of the effect. Eighteen (9 female and 9 male) Children's pythons (Antaresia childreni) each consumed a meal at three temperatures (29 °C, 30 °C, and 31 °C), and gut passage time and digestive efficiency were determined. We found that neither metric was affected by temperature over the range tested. However, digestive efficiency was significantly impacted by the interaction between sex and temperature with males having significantly lower digestive efficiency than females at 31 °C, but not 29 °C or 30 °C. Our results provide insight into the effects of temperature on digestive physiology across narrow temperature ranges as well as demonstrate a sex-based difference in digestive physiology.


Assuntos
Boidae , Fenômenos Fisiológicos do Sistema Digestório , Criança , Masculino , Feminino , Humanos , Animais , Temperatura , Temperatura Alta , Boidae/fisiologia , Água , Temperatura Corporal
13.
PLoS One ; 19(4): e0297217, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635692

RESUMO

This study focuses on isolated thermophilic Bacillus species' adaptability and physiological diversity, highlighting their ecological roles and potential industrial applications. We specifically investigated their capacity to thrive in extreme conditions by examining their environmental tolerances and adaptations at the metabolic and genetic levels. The primary objective is to evaluate the suitability of these species for biotechnological applications, considering their resilience in harsh environments. We conducted a comparative analysis of the environmental adaptability parameters for various Bacillus species. This included examining growth temperature ranges, pH tolerance, oxygen requirements, carbohydrate fermentation patterns, colony morphology, enzymatic activities, and genetic properties. Controlled laboratory experiments provided the data, which were then analyzed to determine patterns of adaptability and diversity. The research revealed that Bacillus species could endure temperatures as high as 73°C, with a generally lower growth limit at 43°C. However, strains TBS35 and TBS40 were exceptions, growing at 37°C. Most strains preferred slightly alkaline conditions (optimal pH 8), but TBS34, TBS35, and TBS40 exhibited adaptations to highly alkaline environments (pH 11). Oxygen requirement tests classified the species into aerobic, anaerobic, and facultative aerobic categories. Genetic analysis highlighted variations in DNA concentrations, 16s rRNA gene lengths, and G+C content across species. Although glucose was the primary substrate for carbohydrate fermentation, exceptions indicated metabolic flexibility. The enzymatic profiles varied, with a universal absence of urease and differences in catalase and oxidase production. Our findings underscore thermophilic Bacillus species' significant adaptability and diversity under various environmental conditions. Their resilience to extreme temperatures, pH levels, varied oxygen conditions, and diverse metabolic and genetic features emphasize their potential for biotechnological applications. These insights deepen our understanding of these species' ecological roles and highlight their potential industrial and environmental applications.


Assuntos
Bacillus , RNA Ribossômico 16S/genética , Temperatura Alta , Oxigênio , Carboidratos , Filogenia
14.
PLoS One ; 19(4): e0299896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568900

RESUMO

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.


Assuntos
Temperatura Alta , Níquel , Preparo de Canal Radicular , Microtomografia por Raio-X/métodos , Preparo de Canal Radicular/métodos , Ligas , Titânio , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/cirurgia , Desenho de Equipamento
15.
Nature ; 628(8006): 110-116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38570715

RESUMO

The emergence of biopolymer building blocks is a crucial step during the origins of life1-6. However, all known formation pathways rely on rare pure feedstocks and demand successive purification and mixing steps to suppress unwanted side reactions and enable high product yields. Here we show that heat flows through thin, crack-like geo-compartments could have provided a widely available yet selective mechanism that separates more than 50 prebiotically relevant building blocks from complex mixtures of amino acids, nucleobases, nucleotides, polyphosphates and 2-aminoazoles. Using measured thermophoretic properties7,8, we numerically model and experimentally prove the advantageous effect of geological networks of interconnected cracks9,10 that purify the previously mixed compounds, boosting their concentration ratios by up to three orders of magnitude. The importance for prebiotic chemistry is shown by the dimerization of glycine11,12, in which the selective purification of trimetaphosphate (TMP)13,14 increased reaction yields by five orders of magnitude. The observed effect is robust under various crack sizes, pH values, solvents and temperatures. Our results demonstrate how geologically driven non-equilibria could have explored highly parallelized reaction conditions to foster prebiotic chemistry.


Assuntos
Biopolímeros , Evolução Química , Temperatura Alta , Origem da Vida , Biopolímeros/química , Dimerização , Glicina/química , Concentração de Íons de Hidrogênio , Nucleotídeos/química , Polifosfatos/química , Solventes/química
16.
Sci Total Environ ; 927: 172304, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604357

RESUMO

Hyperthermophilic composting, characterized by temperatures equal to or exceeding 75 °C, offers superior compost maturity and performance. Inoculation with thermophilic bacteria presents a viable approach to achieving hyperthermophilic composting. This study investigates the effects of inoculating thermophilic bacteria, isolated at different temperatures (50 °C, 60 °C, and 70 °C) into compost on maturity, gaseous emissions, and microbial community dynamics during co-composting. Results indicate that the thermophilic bacteria inoculation treatments exhibited peak temperature on Day 3, with the maximum temperature of 75 °C reached two days earlier than the control treatment. Furthermore, these treatments demonstrated increased bacterial richness and diversity, along with elevated relative abundances of Firmicutes and Proteobacteria. They also fostered mutualistic correlations among microbial species, enhancing network connectivity and complexity, thereby facilitating lignocellulose degradation. Specifically, inoculation with thermophilic bacteria at 60 °C increased the relative abundance of Thermobifida and unclassified-f-Thermomonosporaceae (Actinobacteriota), whereas Bacillus, a thermophilic bacterium, was enriched in the 70 °C inoculation treatment. Consequently, the thermophilic bacteria at 60 °C and 70 °C enhanced maturity by 36 %-50 % and reduced NH3 emissions by 1.08 %-27.50 % through the proliferation of thermophilic heterotrophic ammonia-oxidizing bacteria (Corynebacterium). Moreover, all inoculation treatments decreased CH4 emissions by 6 %-27 % through the enrichment of methanotrophic bacteria (Methylococcaceae) and reduced H2S, Me2S, and Me2SS emissions by 1 %-25 %, 47 %-63 %, and 15 %-53 %, respectively. However, the inoculation treatments led to increased N2O emissions through enhanced denitrification, as evidenced by the enrichment of Truepera and Pusillimonas. Overall, thermophilic bacteria inoculation promoted bacteria associated with compost maturity while attenuating the relationship between core bacteria and gaseous emissions during composting.


Assuntos
Bactérias , Compostagem , Microbiota , Microbiologia do Solo , Compostagem/métodos , Microbiota/fisiologia , Temperatura Alta , Poluentes Atmosféricos/análise
17.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38605681

RESUMO

Heat stress (HS) occurs when exogenous and metabolic heat accumulation exceeds heat dissipation; a thermal imbalance that compromises female reproduction. This study investigated the hypothesis that HS alters the ovarian proteome and negatively impacts proteins engaged with insulin signaling, inflammation, and ovarian function. Prepubertal gilts (n = 19) were assigned to one of three environmental groups: thermal neutral with ad libitum feed intake (TN; n = 6), thermal neutral pair-fed (PF; n = 6), or HS (n = 7). For 7 d, HS gilts were exposed to 12-h cyclic temperatures of 35.0 ±â€…0.2 °C and 32.2 ±â€…0.1 °C, while TN and PF gilts were housed at 21.0 ±â€…0.1 °C. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed on ovarian protein homogenates. Relative to TN gilts, 178 proteins were altered (P ≤ 0.05, log2foldchange ≥ 1) by HS, with 76 increased and 102 decreased. STRING gene ontology classified and identified 45 biological processes including those associated with chaperone protein refolding, cytoplasmic translational initiation, and immune activation; with a protein-protein interaction web network of 158 nodes and 563 edges connected based on protein function (FDR ≤ 0.05). Relative to PF, HS altered 330 proteins (P ≤ 0.05, log2foldchange ≥ 1), with 151 increased and 179 decreased. Fifty-seven biological pathways associated with protein function and assembly, RNA processing, and metabolic processes were identified, with a protein-protein interaction network of 303 nodes and 1,606 edges. Comparing HS with both the TN and PF treatments, 72 ovarian proteins were consistently altered by HS with 68 nodes and 104 edges, with biological pathways associated with translation and gene expression. This indicates that HS alters the ovarian proteome and multiple biological pathways and systems in prepubertal gilts; changes that potentially contribute to female infertility.


Heat stress impairs female fertility, yet the mechanisms underlying reduced fecundity remain unclear. This study investigated the ovarian proteomic changes resultant from heat stress in prepubertal gilts and discovered changes related to several important biological processes that could be responsible for reduced female fertility.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Suínos , Feminino , Animais , Cromatografia Líquida/veterinária , Espectrometria de Massas em Tandem/veterinária , Sus scrofa , Resposta ao Choque Térmico , Temperatura Alta
18.
PLoS One ; 19(4): e0299940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38620031

RESUMO

Injecting carbon dioxide is the most effective means of preventing and extinguishing fires in sealing hazardous areas, but the traditional method slowly and remotely injects carbon dioxide gas into the well after gasification on the ground, which is dependent on the complete mine pipe network without cooling effect. To inject liquid directly from the tank with vacuum interlayer and heat insulating powder for rapid inerting and cooling, a new approach using track mobile platform to go deep into the underground mine disaster area is proposed, so the liquid can be delivered to the nozzle at the end of DN40 large diameter pipe, and the continuous gasification jet can be realized. The experimental results show that: (1) The liquid volume in a tank of vacuum degree within 2.0 Pa and 200 mm interlayer reduced no more than 15.5% after 48 days; (2) Taking the pressure in the tank as the power source, because of environmental differences inside and outside the pipe after 100 m pressure holding delivery, the physical form of liquid and gas could be converted instantly; (3) The continuous discharge time without ice blocking for a tank full of 2 m3 liquid was about 10.5 min under 25 L dual mode nitrogen pressurization, which is 1/12 of injection time after ground gasification; (4) Based on the temperature decrease trend measured at different positions, the cooling characteristics on liquid gasification jet path are quantified, and the calculation formula of temperature changing with time on the center line of liquid gasification jet is obtained. Through this new approach, the integration of vacuum insulated storage, safe mobile transportation, and continuous and rapid release with large flow can be achieved for the liquid carbon dioxide.


Assuntos
Dióxido de Carbono , Incêndios , Incêndios/prevenção & controle , Nitrogênio , Temperatura Alta , Temperatura Baixa
19.
Environ Int ; 186: 108657, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38626496

RESUMO

The increasing frequency of heat waves under the global urbanization and climate change background poses elevating risks of chronic kidney disease (CKD). Nevertheless, there has been no evidence on associations between long-term exposures to heat waves and CKD as well as the modifying effects of land cover patterns. Based on a national representative population-based survey on CKD covering 47,086 adults and high spatial resolution datasets on temperature and land cover data, we found that annual days of exposure to heat waves were associated with increased odds of CKD prevalence. For one day/year increases in HW_975_4d (above 97.5 % of annual maximum temperature and lasting for at least 4 consecutive days), the odds ratio (OR) of CKD was 1.14 (95 %CI: 1.12, 1.15). Meanwhile, stronger associations were observed in regions with lower urbanicity [rural: 1.14 (95 %CI: 1.12, 1.16) vs urban: 1.07 (95 %CI: 1.03, 1.11), Pinteraction < 0.001], lower water body coverage [lower: 1.14 (95 %CI: 1.12, 1.16) vs higher: 1.02 (95 %CI: 0.98, 1.05), Pinteraction < 0.001], and lower impervious area coverage [lower: 1.16 (95 %CI: 1.14, 1.18) vs higher: 1.06 (95 %CI: 1.03, 1.10), Pinteraction = 0.008]. In addition, this study found disparities in modifying effects of water bodies and impervious areas in rural and urban settings. In rural regions, the associations between heat waves and CKD prevalence showed a consistent decreasing trend with increases in both proportions of water bodies and impervious areas (Pinteraction < 0.05). Nevertheless, in urban regions, we observed significant effect modification by water bodies, but not by impervious areas. Our study indicates the need for targeted land planning as part of adapting to the kidney impacts of heat waves, with a focus on urbanization in rural regions, as well as water body construction and utilization in both rural and urban regions.


Assuntos
Mudança Climática , Temperatura Alta , Insuficiência Renal Crônica , Urbanização , China/epidemiologia , Humanos , Insuficiência Renal Crônica/epidemiologia , Temperatura Alta/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Prevalência , Adulto , Idoso
20.
J Exp Biol ; 227(8)2024 Apr 15.
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 occur 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 h. 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 3-fold 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 by over 3-fold at 34°C, potentially exacerbating the impacts of coral bleaching.


Assuntos
Antozoários , Dinoflagelados , Resposta ao Choque Térmico , Simbiose , Antozoários/fisiologia , Antozoários/metabolismo , Animais , Dinoflagelados/fisiologia , Dinoflagelados/metabolismo , Resposta ao Choque Térmico/fisiologia , Nutrientes/metabolismo , Nitrogênio/metabolismo , Compostos de Nitrogênio/metabolismo , Água do Mar/química , Temperatura Alta , Aminoácidos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA