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1.
Ann Bot ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052329

RESUMO

BACKGROUND AND AIMS: Pit pairs and their filter-like partition, i.e. pit membranes, play important roles as water pathways, barriers and regulators in the water-conducting system of angiosperms. In Fraxinus species, the intervessel and vessel-parenchyma pit membranes in sapwood are normally encrusted during winter. Although these encrustations inevitably influence the performance of pits, their properties and functions remain unclear. This study aimed to reveal the morphological and chemical characteristics of encrustations in F. mandshurica in order to deepen understanding of the seasonal encrustation of pit membranes. METHODS: Seasonal and positional variations in the presence and morphology of encrustations were examined by field-emission scanning electron microscopy (FE-SEM). Cryo-FE-SEM for freeze-fixed greenwood samples was conducted to clarify whether encrustations were present in living trees. Chemical components were examined by histochemical staining using light and electron microscopies, immunofluorescence labelling and ultraviolet microspectroscopy. KEY RESULTS: Encrustations began to deposit in fall before leaf senescence and disappeared in spring before bud flushing. They infiltrated within the pit membranes, which suggested that they severely limit the permeation of pits. The encrustations differed in morphology among positions: they entirely filled the pit chambers in latewood, while they covered the pit membranes in earlywood. The encrustations were similarly observed in the samples that were freeze-fixed immediately after collection, indicating that they are present in living trees. The encrustations contained polysaccharides, including xyloglucan and homogalacturonan, and phenolic compounds, possibly including flavonoids and coumarins. These chemical components were also detected in droplets found in the latewood vessels with the encrustations, suggesting that the materials constituting encrustations were supplied through the vessel lumens. CONCLUSIONS: Encrustations undoubtedly cover the pit membranes in living F. mandshurica trees in winter and their morphology and chemical composition indicate that they are impermeable, have positional differences in function and are characterised by elaborate deposition/removal processes.

2.
J Plant Res ; 137(2): 179-190, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244125

RESUMO

This study examined the seasonal and diurnal variations in soil respiration rates (RS) during a growing season at the treeline ecotone (2,800 m) and the lower distribution limit (1,600 m) of subalpine forests on a volcanic mountain in Japan. The aboveground biomass, the total RS during the growing season, and the RS per day during the growing season were lower at 2,800 m than those at 1,600 m. Seasonal RS variations positively correlated with those of soil and air temperatures at both elevations, and this tendency was more apparent at 1,600 m than 2,800 m. The mean volumetric soil water content (WS) during the growing season was much lower at 2,800 m than 1,600 m because of the scoria substrate at 2,800 m. The monthly mean diel cycle of RS was positively correlated with the soil temperature at each elevation every month, whereas that at 1,600 m was negatively correlated with that of the WS. The RS at 2,800 m decreased during the daytime especially in August, despite no changes in the WS. The decrease in RS after precipitation at 1,600 m was higher than that at 2,800 m. Seasonal and diurnal RS variations could be reproduced from soil and air temperatures, and WS. Estimating soil respiration rate from these variables will help understand the future carbon budget of forests due to global warming.


Assuntos
Taxa Respiratória , Solo , Solo/química , Estações do Ano , Florestas , Temperatura , China
3.
J Hazard Mater ; 469: 133925, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38432096

RESUMO

This review offers a comprehensive overview of the occurrence, fate, and ecological risk associated with six major categories of antibiotics found in influent, effluent, and sludge from urban wastewater treatment plants (WWTPs) in China. Further exploration includes examining the correlation between antibiotic residual rates in the effluents and process parameters of urban WWTPs across the country. Lastly, a nationwide and urban cluster-specific evaluation of the ecological risk posed by antibiotics in WWTPs is conducted. The findings reveal that the average concentrations of antibiotics in influent, effluent, and sludge from urban WWTPs in China are 786.2 ng/L, 311.2 ng/L, and 186.8 µg/kg, respectively. Among the detected antibiotics, 42% exhibit moderate to high ecological risk in the effluent, with ciprofloxacin, sulfamethoxazole, erythromycin, azithromycin, and tetracycline posing moderate to high ecological risks in sludge. The current biological treatment processes in WWTPs demonstrate inefficacy in removing antibiotics. Hence, there is a pressing need to develop and integrate innovative technologies, such as advanced oxidation processes. This review aims to offer a more comprehensive understanding and identify priority antibiotics for control to effectively manage antibiotic pollution within WWTPs at both national and regional levels.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Antibacterianos/análise , Águas Residuárias , Esgotos , Eliminação de Resíduos Líquidos , Monitoramento Ambiental , Poluentes Químicos da Água/análise , China
4.
Sci Total Environ ; 949: 174898, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39059644

RESUMO

Carbon cycling in coastal wetland soil is controlled by a complex interplay between microbial processes and porewater chemistry that are often influenced by various external forcings like wind, river discharge, and sea-level changes, where most of the organic carbon is mineralized to its inorganic form by various aerobic and anaerobic respiration pathways. The export of this inorganic carbon (DIC) from coastal wetlands has long been recognized as a significant component of the global carbon cycle. The major objective of this work is to determine the relative contribution of various respiration pathways to seasonal DIC production in two contrasting marshes (brackish and salt). The DIC fluxes estimates for the brackish and salt marshes were found to range between 36.52 ± 5.81 and 33.98 ± 2.21 mmol m-2 d-1 in winter and 133.10 ± 102.60 and 82.37 ± 30.87 mmol m-2 d-1 during summer of 2020. For the brackish marsh, aerobic respiration and iron reduction were found to be the primary contributors to DIC production representing 17.91-35.21 % and 61.13-81.97 % of total measured organic matter (OM) respiration respectively. On the other hand, aerobic respiration and sulfate reduction were the primary contributors to DIC production in the salt marsh, accounting for 37.91-83.93 % and 15.87-62.04 % of the total measured OM respiration respectively. The Mississippi River Deltaic Plain experiences high relative sea level rise and expected to undergo rapid change in salinity regime in near future from additional changes in river discharge, proposed sediment diversion plans, and storm surge intensities. The current study represents the first attempt to concurrently estimate various respiration pathways in this region and more studies are needed to understand the trajectories of soil OM respiration pathways and its impact on coastal carbon cycling.

5.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1407245

RESUMO

Resumen Introducción: El Pacífico Norte de Costa Rica es una región diversa y productiva; sin embargo, tenemos un escaso conocimiento sobre el estado de los recursos marinos y la dinámica pesquera, particularmente de la pesca artesanal en el Golfo de Santa Elena, uno de los principales caladeros de la zona. Objetivo: Caracterizar la dinámica de esta pesquería. Métodos: Se analizaron los datos recopilados por el Instituto Costarricense de Pesca y Acuicultura y las facturas pesqueras de los sitios de desembarque para el período 2010-2019. Resultados: Hubo una alta variación en la biomasa desembarcada, sin embargo, la captura total por unidad de esfuerzo (CPUE; kg/día) y de las principales especies objetivo no disminuyó significativamente. En general, hubo una CPUE más baja en los meses de surgencia (diciembre-abril). De las 42 especies comerciales reportadas, la mayor biomasa provino del pargo mancha (Lutjanus guttatus; 22 % de la biomasa), el pargo seda (L. peru; 18 %), las cabrillas (Epinephelus spp.; 15 %) y el pulpo (Octopus spp., 13 %). Conclusiones: La CPUE en Santa Elena no ha disminuido significativamente de 2010 a 2019, pero disminuye en la época de surgencia.


Abstract Introduction: The North Pacific of Costa Rica is a diverse and productive region; however, we have a poor understanding of the status of marine resources and fisheries dynamics, particularly for the artisanal fishery in the Gulf of Santa Elena, one of the main fishing grounds of the area. Objective: To characterize the dynamics of this fishery. Methods: We analyzed data collected by the Instituto Costarricense de Pesca y Acuicultura, and sales invoices from landing sites for the period 2010-2019. Results: There was high variation in the landed biomass, however, total catch per unit effort (CPUE; kg/day) and of the main targeted species did not decrease significantly. Overall, there was a lower CPUE in upwelling months (December-April). For the 42 commercial species reported, most biomass was from the spotted rose snapper (Lutjanus guttatus; 22 % of biomass), the Pacific red snapper (L. peru; 18 %), groupers (Epinephelus spp.; 15 %) and octopuses (Octopus spp., 13 %). Conclusions: CPUE at Santa Elena has not declined significantly from 2010 to 2019, but it falls in the upwelling season.


Assuntos
Animais , Indústria Pesqueira , Análise Espaço-Temporal , Costa Rica
6.
Artigo em Inglês | WPRIM | ID: wpr-205047

RESUMO

PURPOSE: To investigate whether seasonal changes occurred in lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH). METHODS: Patients aged 50 years and older with BPH treated with α1-blockers were enrolled. The International Prostate Symptom Score (IPSS), quality of life (QoL) score, maximum and average flow rate, voided volume, and postvoid residual volume were measured in summer and winter. RESULTS: A total of 164 patients were enrolled. The total IPSS and QoL index did not show a significant difference between the 2 seasons. When the IPSS was divided into storage symptoms and voiding symptoms, storage symptoms in winter were substantially but nonsignificantly higher than those in summer (P=0.056). Of the 7 individual symptoms in the IPSS, a significant seasonal difference was observed only for nocturia, with a higher score in winter. Moreover, none of the uroflowmetric parameters showed a seasonal change. Voided volume had significant correlations with each symptom (urgency and nocturia) and overall subjective scores (storage, total IPSS, and QoL) exclusively in summer, while this correlation remained only for nocturia in winter. CONCLUSIONS: As it has generally been assumed that LUTS deteriorate in winter, the present study corroborated that the severity of storage symptoms was higher in winter than in summer, even in patients treated with α₁-blockers. In contrast, a seasonal difference was not observed in the uroflowmetric parameters, which may be partly due to the loss of the correlation between subjective and objective measurements of storage symptoms in winter.


Assuntos
Humanos , Masculino , Antagonistas Adrenérgicos alfa , Povo Asiático , Sintomas do Trato Urinário Inferior , Noctúria , Próstata , Hiperplasia Prostática , Qualidade de Vida , Volume Residual , Estações do Ano , Urodinâmica
7.
Artigo em Inglês | WPRIM | ID: wpr-913221

RESUMO

  Background: This study aimed to clarify the effects of bathing on cardiovascular and psychological responses during winter and summer, focusing on three different time points (immediately after entering the bathtub, during bathing, and immediately after leaving the bathtub).   Methods: Ten young (29.6 ± 1.5 years) individuals were asked to bathe for 20 min with 40℃ hot water in summer and with 42℃ hot water in winter. The room temperature and humidity in winter were 20.1℃ and 56.7%, while those in summer were 27.0℃ and 58.3%, respectively. Tympanic temperature (Tty) was measured using a thermistor thermometer; systolic blood pressure (SBP) and diastolic blood pressures (DBP) and heart rate (HR) were measured using an auto-sphygmomanometer, and double product (DP) was calculated using the value of HR multiplied by SBP value. Subjective thermal and comfortable sensations were evaluated using a seven-point rating scale.   Results: Results showed a significant increases in SBP values in both seasons immediately after bathing. In winter, DP increased significantly after bathing. Meanwhile, no significant differences were observed in all parameters immediately after bathing between winter and summer. On the contraly, significant differences were observed in Tty, HR, and DP value between winter and summer during bathing. HR and DP values in winter were significantly lower than those in summer immediately after leaving the bathtub. A relationship between thermal sensation and comfortable sensation was observed in both seasons, but the strength of the relationship was more relevant in summer than in winter.   Conclusion: The effects of bathing in 42℃ hot water on the cardiovascular system in winter are greater than those in 40℃ hot water in summer. The high temperature of the bath water may not produce as much discomfort during winter than that during summer, therefore bathing time may be longer.

8.
Artigo em Inglês | WPRIM | ID: wpr-837446

RESUMO

  Background: This study aimed to clarify the effects of bathing on cardiovascular and psychological responses during winter and summer, focusing on three different time points (immediately after entering the bathtub, during bathing, and immediately after leaving the bathtub).   Methods: Ten young (29.6±1.5 years) individuals were asked to bathe for 20 min with 40°C hot water in summer and with 42°C hot water in winter. The room temperature and humidity in winter were 20.1°C and 56.7%, while those in summer were 27.0°C and 58.3%, respectively. Tympanic temperature (Tty) was measured using a thermistor thermometer; systolic blood pressure (SBP) and diastolic blood pressures (DBP) and heart rate (HR) were measured using an auto-sphygmomanometer, and double product (DP) was calculated using the value of HR multiplied by SBP value. Subjective thermal and comfortable sensations were evaluated using a seven-point rating scale.   Results: Results showed a significant increases in SBP values in both seasons immediately after bathing. In winter, DP increased significantly after bathing. Meanwhile, no significant differences were observed in all parameters immediately after bathing between winter and summer. On the contraly, significant differences were observed in Tty, HR, and DP value between winter and summer during bathing. HR and DP values in winter were significantly lower than those in summer immediately after leaving the bathtub. A relationship between thermal sensation and comfortable sensation was observed in both seasons, but the strength of the relationship was more relevant in summer than in winter.   Conclusion: The effects of bathing in 42°C hot water on the cardiovascular system in winter are greater than those in 40°C hot water in summer. The high temperature of the bath water may not produce as much discomfort during winter than that during summer, therefore bathing time may be longer.

9.
Artigo em Chinês | WPRIM | ID: wpr-459661

RESUMO

Objective To study the seasonal changes of glucose levels per unit soft tissue of Oncomelania hupensis. Meth-ods O. hupensis snails were collected from the beach of the Qingyi River in Wuhu City,Anhui Province from August 2012 to July 2013. They were kept in minus 80℃refrigerator immediately. The male snails were distinguished from female,and their soft tissues were collected separately after crushing their shells. The hexokinase method was used to measure the glucose concen-trations,and the results were analyzed statistically. Results The contents of glucose decreased from March to July. The lowest glucose content in the female was 1.87μg/mg in March,and that in male was 3.70μg/mg in July. Both of them increased from August and reached peak levels in September(♀=57.38μg/mg,♂=44.39μg/mg),and then gradually decreased from Octo-ber to next January and increased in February. Conclusion The contents of glucose have seasonal changes regularly in O. hu-pensis.

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