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Objective: To examine the relationship between pregnancy-related anxiety, family functions, and sleep quality, and to determine whether family functions mediate the relationship between pregnancy-related anxiety and sleep quality. Methods: A cross-sectional survey was conducted on pregnant women between April to August in 2022 in the obstetrics outpatient clinic of a tertiary care hospital in the Ningxia Hui Autonomous Region of China. A total of 1014 pregnant women aged 18 years and older were surveyed. They completed questionnaires, including: general demographic characteristics, the Pregnancy-related anxiety scale (PAQ), the Family Adaptation, Partnership, Growth, Affection, and Resolve (APGAR), and the Pittsburgh Sleep Quality Index Questionnaire (PSQI). Model 4 in PROCESS was used to analyze the relationships among pregnancy-related anxiety, family functions, and sleep quality, with family functions as a mediator. Results: Among the 1014 pregnant women, the pregnancy-related anxiety scale score was (21.84 ± 5.64). The total score of the family functions scale was (8.10±2.26), and the overall sleep quality scale score was (7.89±2.99). When participants were grouped according to different socio-demographic characteristics, the study showed that all variables differed from anxiety, family functions or sleep quality, except for age, pre-pregnancy BMI and whether or not they had a first birth, which was not associated with anxiety, family functions, or sleep quality (P<0.05). The pregnancy-related anxiety was positively associated with sleep quality (P<0.01), while family functions were negatively associated with sleep quality (P<0.01). In addition, family functions mediate the relationship between pregnancy-related anxiety and sleep quality during pregnancy, on the first and second trimesters, intermediation rate is 9.31% (P<0.05), and on the third trimesters, intermediation rate is 21.38% (P<0.05). Conclusion: Pregnancy- related anxiety is a risk factor for sleep quality, however, family functions are protective factors for sleep quality. Family functions play an intermediary role in sleep quality caused by pregnancy-related anxiety, especially on the third trimesters. This finding may provide a scientific basis for developing intervention strategies to improve the sleep quality of pregnant women.
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Maternal immune activation (MIA), defined as elevated levels of inflammatory markers beyond the normal range, can occur due to psychological stress, infection, and other disruptions during pregnancy. MIA affects the immune system development in offspring and increases the risk of immune-related disorders. Limited studies have investigated the effects of prenatal stress on offspring's immune system. In this study, pregnant rats were exposed to chronic unpredictable mild stress (CUMS) during pregnancy, involving seven different stressors. We examined the impact of prenatal stress stimuli on the offspring's immune system and observed activation of the PI3K/Akt/NF-κB signaling pathway, resulting in an imbalance of Th17/Treg cells in the offspring's spleen. Our findings revealed increased plasma levels of corticosterone, IL-1ß, and IL-6 in female rats exposed to prenatal stress, as well as elevated serum levels of IL-6 and TNF-α in the offspring. Furthermore, we identified a correlation between cytokine levels in female rats and their offspring. Transcriptome sequencing and qPCR experiments indicated differentially expressed mRNAs in offspring exposed to prenatal stress, which may contribute to the imbalance of Th17/Treg cells through the activation of the Gng3-related PI3K/Akt/NF-κB pathway.
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FN-kappa B , Proteínas Proto-Oncogénicas c-akt , Embarazo , Ratas , Femenino , Animales , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Interleucina-6 , Linfocitos T Reguladores/metabolismo , Transducción de SeñalRESUMEN
To investigate the effects of short-term nitrogen (N) deposition on organic matter composition of litter and soil in Moso bamboo (Phyllostachys edulis) forests, we established a N-addition treatments (50 kg N·hm-2·a-1) to simulate the ambient and N deposition in a subtropical Moso bamboo forest from July 2020 to January 2022. We analyzed the organic matter composition of Moso bamboo leaf/root litter and soil by using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique. The results showed that short-term N deposition significantly increased the relative content of soil phenols by 50.9%, while significantly decreased fatty acids by 26.3%. The rela-tive content of alkanes & alkenes and lignin in leaf litter was significantly increased by 51.9% and 33.5%, respectively, while that of phenols and polysaccharides significantly decreased by 52.2% and 56.3%. In root litter, eleva-ted N significantly decreased the relative content of polycyclic aromatic hydrocarbons by 16.6%. Moreover, the relative content of fatty acids in soil organic matter was significantly positively correlated with the relative content of poly-saccharides in leaf litter. The relative content of phenols in soil organic matter was significantly positively correlated with the relative content of lignin, and negatively correlated with the relative content of polysaccharides in leaf litter. Our results demonstrated that short-term N deposition did not change the concentration of total organic carbon, total nitrogen, and C/N of the soil, leaf litter, and root litter, but significantly altered the chemical composition of organic matter. In addition, the changes in chemical composition of organic matter in soil under short-term N deposition were affected by the composition of organic matter in leaf litter.
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Nitrógeno , Suelo , Suelo/química , Nitrógeno/análisis , Lignina , Poaceae , Bosques , Fenoles , Ácidos Grasos , Polisacáridos , Carbono/análisisRESUMEN
PURPOSE: Colloid and/or co-load may be more effective than crystalloid for preventing postspinal anesthesia hypotension. We tested five different prophylactic norepinephrine dosages combined with colloid co-load infusion in patients receiving cesarean section and spinal anesthesia. METHODS: Patients were randomly allocated to receive different prophylactic norepinephrine dosages (0 [NE 0 group], 0.025 [NE 25 group], 0.05 [NE 50 group], 0.075 [NE 75 group], or 0.1 [NE 100 group] µg/kg/min) combined with 500 mL 6% hydroxyethyl starch (130/0.4) immediately following spinal anesthesia (n = 35 per group). The primary endpoint was the incidence of postspinal anesthesia hypotension (systolic blood pressure [SBP] < 80% of baseline). Secondary endpoints included severe hypotension, bradycardia, nausea or vomiting, hypertension, SBP stability control versus baseline, the 50% (effective dose, ED50) and 90% (ED90) dose effective for preventing postspinal anesthesia hypotension, Apgar scores, and umbilical cord blood gases. RESULTS: The incidence of postspinal anesthesia hypotension was 48.6%, 31.3%, 17.1%, 14.3%, and 5.7% in the respective groups. As the prophylactic norepinephrine dosage increased, the incidence of postspinal anesthesia hypotension declined (p < 0.001), and SBP remained stable relative to baseline (median performance error [MDPE], p < 0.001; median absolute performance error [MDAPE], p = 0.001). The ED50 and ED90 values were -0.006 (95% CI -0.046-0.013) and 0.081 (95% CI 0.063-0.119) µg/kg/min. Other endpoints were comparable across the groups. CONCLUSION: An initial prophylactic norepinephrine dosage of 0.05 µg/kg/min combined with 500 mL 6% hydroxyethyl starch (130/0.4) co-load infusion was optimal for preventing postspinal anesthesia hypotension during cesarean section. TRIAL REGISTRATION: NCT05133817, registration date: 12 Nov, 2021.
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Background: Norepinephrine and phenylephrine are widely used for obstetric anesthesia. Our central objective was to determine the ED (effective dose) 90 and potency ratio of prophylactic norepinephrine and phenylephrine boluses for preventing postspinal anesthesia hypotension during cesarean section. Methods: Patients scheduled for elective cesarean section (n = 80) were randomly allocated to receive prophylactic norepinephrine (NE) or phenylephrine (PE) boluses immediately after induction of spinal anesthesia. An initial dose of NE (3 µg) and PE (37.5 µg) was given to the first patient, and an up-and-down sequential allocation method was used to determine the next dose level according to the responses (the effectiveness for preventing postspinal anesthesia hypotension [defined as SBP < 80% of baseline value]). Primary outcomes were ED90 and the potency ratio of prophylactic norepinephrine and phenylephrine boluses. Secondary outcomes were the incidence of postspinal anesthesia hypotension, severe postspinal anesthesia hypotension, nausea, vomiting, bradycardia, hypertension, umbilical artery blood gas values, and Apgar scores. Results: The ED90 values for prophylactic norepinephrine and phenylephrine boluses were 8.0 µg (95% CI 7.1-11.0 µg) and 90.9 µg (95% CI 82.0-123.9 µg), respectively. The estimated relative potency ratio was 11.4:1. The incidence of bradycardia was lower in the NE group (2.5% vs 20%, P = 0.034). Other outcomes were comparable between the two groups. Conclusion: An 8-µg prophylactic bolus of norepinephrine and a 90-µg prophylactic bolus of phenylephrine can effectively prevent postspinal anesthesia hypotension in patients during cesarean section.
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Anestesia Obstétrica , Anestesia Raquidea , Hipotensión , Humanos , Embarazo , Femenino , Fenilefrina , Norepinefrina , Cesárea/efectos adversos , Cesárea/métodos , Bradicardia , Hipotensión/inducido químicamente , Hipotensión/prevención & control , Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Anestesia Raquidea/métodos , Método Doble Ciego , VasoconstrictoresRESUMEN
Background: Chronic long-term stress is associated with a range of disorders, including depression and a variety of other chronic illnesses. It is well known that maternal exposure to psychosocial stress during pregnancy significantly increases the likelihood of adverse pregnancy outcomes. The gut microbiota has been a popular topic, it is a key mediator of the gut-brain axis and plays an important role in human health; changes in the gut microbiota have been related to chronic stress-induced health impairment, however, the relationship between maternal negative emotions and abnormal gut microbiota and its metabolites during maternal exposure to chronic stress during pregnancy remains unclear. Methods: Pregnant rats were subjected to chronic unpredicted mild stress (CUMS) to establish the rat model of chronic stress during pregnancy. The behavioral changes were recorded using sucrose preference test (SPT) and open-field test (OFT), plasma corticosterone levels were determined by radioimmunoassay, and a comprehensive method combining 16S rRNA gene sequencing and gas chromatography-mass spectrometry (GC-MS) metabolomics was used to study the effects of stress during pregnancy on the function of intestinal microbiota and its metabolites. Results: Chronic stress during pregnancy not only increased maternal plasma corticosterone (P < 0.05), but also caused maternal depression-like behaviors (P < 0.05). Chronic stress during pregnancy changed the species composition at the family level of maternal gut microbiota, the species abundance of Ruminococcaceae in the stress group (23.45%) was lower than the control group (32.67%) and the species abundance of Prevotellaceae in the stress group (10.45%) was higher than the control group (0.03%) (P < 0.05). Vertical locomotion and 1% sucrose preference percentage in pregnant rats were negatively correlated with Prevotellaceae (r = - 0.90, P < 0.05). Principal component analysis with partial least squares discriminant analysis showed that the integration points of metabolic components in the stress and control groups were completely separated, indicating that there were significant differences in the metabolic patterns of the two groups, and there were seven endogenous metabolites that differed (P < 0.05). Conclusions: The negative emotional behaviors that occur in pregnant rats as a result of prenatal chronic stress may be associated with alterations in the gut microbiota and its metabolites. These findings provide a basis for future targeted metabolomics and gut flora studies on the effects of chronic stress during pregnancy on gut flora.
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Microbioma Gastrointestinal , Humanos , Embarazo , Femenino , Ratas , Animales , ARN Ribosómico 16S/genética , Corticosterona , Metabolómica , EmocionesRESUMEN
Numerous clinical and animal studies have found that antenatal chronic stress can lead to pathological changes the hippocampal development from embryos to adult, but the mechanisms are not well understood. Proteomic analyses provide a new insight to explore the potential mechanisms of this impairment. In this study, gestating rats were subjected to chronic unpredictable mild stress (CUMS) during pregnant days using nine different stimulations, and the changes of the learning and memory performance and the expression of proteins in the hippocampus of offspring were measured. It was found that prenatal chronic stress led to growth retardation, impaired spatial learning and memory ability in the offspring. Furthermore, prenatal stress caused various degrees of damage to neurons, Nissl body, mitochondria and synaptic structures in hippocampal CA3 region of offspring. In addition, 26 significantly different expressed proteins (DEPs) were found between the two groups by using isoquantitative tag-based relative and absolute quantification (iTRAQ) proteomics analysis. Further analyses of these DEPs showed that involved with different molecular functions and several biological processes, such as biological regulation and metabolic processes. Among these, the KEGG pathway enrichment showed that learning and memory impairment was mainly associated with the cyclic guanosine monophosphate protein kinase G (cGMP-PKG) pathway. At the same time, compared with OPC group, the NO, nNOS and cGMP level were significantly decreased, and the expression of PKG protein was also dropped. All of these results suggested that pregnant rats exposed to chronic psychological stress might impair spatial learning and memory ability of offspring, by disturbing the NO/cGMP/PKG signaling pathway.
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Hipocampo , Proteómica , Animales , GMP Cíclico/metabolismo , Femenino , Hipocampo/metabolismo , Trastornos de la Memoria/etiología , Embarazo , Ratas , Aprendizaje EspacialRESUMEN
China produces a large amount of industrial effluent with multiple pollutants contained, along with a flourishing economy. This study aims to examine the dynamics between China's industrialization and accompanying environmental pressure based on the gray water footprint (GWF) concept. A newly proposed net GWF (NetGWF) and the decoupling index (DI) are applied to evaluate China's industrial activities during 2002-2015 in different modes considering typical, all, and individual pollutants. The NetGWF dynamics are further quantitatively decomposed into 17 effects of not only commonly assessed drivers but also industrial fixed capital formation, inventory variation, and import, using an advanced dynamic decomposition analysis approach. Results show NetGWF is an effective indicator measuring domestic water pollution stress from industrialization, with NetGWF-AllPlt (estimated using all pollutants) validated to be more reliable and sensitive than NetGWF-COD&NH3N (estimated using Chemical oxygen demand and Ammonia nitrogen). An overall decoupling between China's industrialization and wastewater pollution is identified with most of DIs less than 1.0 caused mainly by decreased (by around 40%) industrial NetGWFs for 2002-2015. Industrial fixed capital formation and export have caused main components of China's industrial GWF, with proportions of 37.3% and 30.8%, respectively, followed by urban household consumption (16.8%). Volatile phenol, Petroleum, and Ammonia nitrogen are recognized as three decisive contaminants to the industrial NetGWFs. Technological development is the dominant contributor (-50%) to decreasing China's industrial NetGWFs, while fixed capital formation (18%) and export (16%) are principal drivers increasing the NetGWFs. Based on these, we expect to provide informative findings for building a pollution-decoupled industrialization.
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Contaminantes Ambientales , Desarrollo Industrial , Análisis de la Demanda Biológica de Oxígeno , China , Agua , Contaminación del AguaAsunto(s)
Anestesia Obstétrica , Anestesia Raquidea , Hipotensión , Preeclampsia , Bradicardia/inducido químicamente , Cesárea , Femenino , Humanos , Hipotensión/prevención & control , Norepinefrina/uso terapéutico , Fenilefrina/uso terapéutico , Preeclampsia/tratamiento farmacológico , Embarazo , Vasoconstrictores/uso terapéuticoRESUMEN
STUDY OBJECTIVE: Prophylactic norepinephrine infusion effectively lowers the incidence of postspinal anesthesia hypotension. The optimal prophylactic dose of norepinephrine remains undefined. The purpose of this study was to investigate the optimal prophylactic dose of norepinephrine to prevent postspinal anesthesia hypotension in patients undergoing cesarean section. DESIGN: Prospective, double-blind, randomized, controlled, dose-finding trial. SETTING: Operating room from March 2020 to June 2020. PATIENTS: Ninety nine primipara or multipara women 18 - 40 years of age, singleton pregnancy ≥ 37 weeks, American Society of Anesthesiologists' physical status 1 or 2, scheduled for elective cesarean section under spinal anesthesia were included in this study. INTERVENTION: Patients were randomly assigned into groups to receive normal saline (NS) or one of four different prophylactic doses (0.025 [NE25], 0.05 [NE50], 0.075 [NE75], and 0.1 [NE100] ug/kg/min) of norepinephrine. The primary end point was the incidence of postspinal anesthesia hypotension (systolic blood pressure [SBP] < 80% of baseline) within 15 min after spinal anesthesia. Secondary outcomes included the overall stability of SBP control versus baseline (median performance error [MDPE] and median absolute performance error [MDAPE]), the dose that would be effective in preventing postspinal anesthesia hypotension in 50% (effective dose, ED 50) and 90% (ED90) of patients, other adverse events (bradycardia, nausea, vomiting, hypertension, and the total additional bolus of norepinephrine and atropine), and neonatal outcomes (blood gas values and Apgar scores). MEASUREMENTS AND MAIN RESULTS: The incidence of postspinal anesthesia hypotension in NS, NE25, NE50, NE75, and NE100 groups was 68.42% (13/19), 40.00% (8/20), 20.00% (4/20), 15.00% (3/20), and 10.00% (2/20), respectively. With increasing prophylactic doses of norepinephrine, the incidence of postspinal anesthesia hypotension decreased (p < 0.001), SBP was maintained closer to the baseline (MDPE, p < 0.001; MDAPE, p = 0.001), and the total additional bolus of norepinephrine decreased (p < 0.001). The ED50 and ED90 values of norepinephrine were 0.016 (95% CI: -0.014 - 0.033) and 0.088 (95% CI: 0.068 - 0.133) ug/kg/min, respectively. Other adverse effects, neonatal outcomes, and the total additional bolus of atropine did not differ among the five groups. CONCLUSIONS: A prophylactic dose of 0.05 or 0.075 µg/kg/min norepinephrine prevents postspinal anesthesia hypotension in patients undergoing cesarean section.
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Anestesia Raquidea , Cesárea , Hipotensión , Norepinefrina , Adolescente , Adulto , Anestesia Raquidea/efectos adversos , Método Doble Ciego , Femenino , Humanos , Hipotensión/inducido químicamente , Hipotensión/prevención & control , Infusiones Intravenosas , Norepinefrina/administración & dosificación , Embarazo , Estudios Prospectivos , Vasoconstrictores/administración & dosificación , Adulto JovenRESUMEN
River algal blooms have become a challenging environmental problem worldwide due to strong interference of human activities and megaprojects (e.g., big dams and large-scale water transfer projects). Previous studies on algal blooms were mainly focused on relatively static water bodies (i.e., lakes and reservoirs), but less on the large rivers. As the largest tributary of the Yangtze River of China and the main freshwater source of the South-to-North Water Diversion Project (SNWDP), the Han River has experienced frequent algal blooms in recent decades. Here we investigated the algal blooms during a decade (2003-2014) in the Han River by two gradient boosting machine (GBM) models with k-fold cross validation, which used explanatory variables from current 10-day (GBMc model) or previous 10-day period (GBMp model). Our results advocate the use of GBMp due to its higher accuracy (median Kappa = 0.9) and practical predictability (using antecedent observations) compared to GBMc. We also revealed that the algal blooms in the Han River were significantly modulated by antecedent water levels in the Han River and the Yangtze River and water level variation in the Han River, whereas the nutrient concentrations in the Han River were usually above thresholds and not limiting algal blooms. This machine-learning-based study potentially provides scientific guidance for preemptive warning and risk management of river algal blooms through comprehensive regulation of water levels during the dry season by making use of water conservancy measures in large rivers.
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Monitoreo del Ambiente , Ríos , China , Eutrofización , Humanos , LagosRESUMEN
OBJECTIVE: To investigate the efficacy and safety of prophylactic infusion of norepinephrine (NE) versus normal saline in patients undergoing cesarean section. METHODS: Patients (n = 97) were randomized to receive a bolus of NE (6 µg) immediately following spinal anesthesia with maintenance NE (0.05 µg/kg/min IV) or normal saline (n = 98). The primary endpoint was the incidence of postspinal anesthesia hypotension [systolic blood pressure (SBP) < 80% of baseline] at 1-20 min following spinal anesthesia. Secondary outcomes were the overall stability of SBP control versus baseline, inferior vena cava collapsibility index (IVC-CI), other adverse events (bradycardia, nausea, vomiting, and hypertension), and neonatal outcomes (blood gas values and Apgar scores). RESULTS: The rates of postspinal anesthesia hypotension and severe postspinal anesthesia hypotension (SBP < 60% of the baseline) were significantly lower in the NE group (17.5% vs. 62.2%, p < 0.001; 7.2% vs. 17.4%, p = 0.031). In the NE group, SBP remained more stable and closer to baseline (p < 0.001), and IVC-CI values were lower 5 min after spinal anesthesia and 5 min after fetal delivery (p = 0.045; p < 0.001, respectively). Other adverse effects and neonatal outcomes were not different between the two groups. CONCLUSION: Prophylactic NE infusion effectively lowers the incidence of postspinal anesthesia hypotension and does not increase other adverse events in patients or neonates.
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Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Cesárea/efectos adversos , Hipotensión/prevención & control , Infusiones Parenterales/efectos adversos , Norepinefrina/administración & dosificación , Profilaxis Pre-Exposición/métodos , Vasoconstrictores/administración & dosificación , Adulto , Anestesia Obstétrica/métodos , Anestesia Raquidea/métodos , Presión Sanguínea , Bradicardia/inducido químicamente , Bradicardia/epidemiología , Cesárea/métodos , China/epidemiología , Femenino , Humanos , Hipertensión/inducido químicamente , Hipertensión/complicaciones , Hipotensión/epidemiología , Recién Nacido , Infusiones Parenterales/métodos , Persona de Mediana Edad , Náusea/inducido químicamente , Náusea/epidemiología , Norepinefrina/efectos adversos , Embarazo , Resultado del Tratamiento , Vasoconstrictores/efectos adversos , Vómitos/inducido químicamente , Vómitos/epidemiología , Adulto JovenRESUMEN
Approximately 94% of the land area of the Northern Tibetan Plateau is covered by grasslands, which comprise one of five key livestock producing regions in China. In contrast to most other regions worldwide, these alpine grasslands are much more sensitive to global climate change, thus they are under intense study. The differences in species diversity, plant biomass, and soil properties of five representative's alpine grassland types in the Northern Tibetan Plateau were investigated in this research. The results revealed that 11 community types were identified according to the importance of dominant species and constructive species. There were significant differences in the Margalef index (H), Simpson diversity index (D), Shannon-wiener diversity index (H'), and Pielou evenness index (J) indices between these five alpine grasslands. Further, the above-ground biomass (AGB), below-ground biomass (BGB), total biomass (TB), root:shoot (R/S) ratio, and coverage showed significant differences in 5 alpine grasslands. There were also considerable variations in the pH, total nitrogen concentration (TN), total phosphorus concentration (TP), soil organic carbon (SOC) and C-to-N ratio (C:N) among the five alpine grasslands. The highest value of biomass and soil characteristics was always in the alpine steppe (AS), or AM, while the lowest of that was in the alpine desert steppe (ADS), or alpine desert (AD). Moreover, there were significant differences in the soil particle size fractions between the five alpine grasslands. In the AM and AS, the dominant soil particle was clay, while in the alpine meadow-steppe (AMS), ADS, and AD it was fine and medium sand. Substantial correlations were found between the biomass and species diversity indices H, D or H' and soil TN, TP, or SOC. Moreover, silt had a significantly positive correlation with soil C:N, BGB, TB, and R/S, while medium sand and coarse sand was significant negatively correlated. With regard to these grassland types, it is proposed that the AM or AS may be an actively changing grassland types in the Northern Tibetan Plateau.
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Biodiversidad , Biomasa , Pradera , Suelo/química , Concentración de Iones de Hidrógeno , Nitrógeno/análisis , Raíces de Plantas/fisiología , Brotes de la Planta/fisiología , Plantas/química , Plantas/metabolismo , TibetRESUMEN
Squalene is found in a large number of plants, animals, and microorganisms, as well as other sources, playing an important role as an intermediate in sterol biosynthesis. It is used widely in the food, cosmetics, and medicine industries because of its antioxidant, antistatic, and anti-carcinogenic properties. A higher natural squalene component of lipids is usually reported as being isolated to organisms living in harsh environments. In the Tibetan Plateau, which is characterized by high altitude, strong solar radiation, drought, low temperatures, and thin air, the squalene component was identified in five alpine grasslands soils using the pyrolysis gas chromatographyâ»mass spectrometry (Py-GC/MS) technique. The relative abundance of squalene ranged from 0.93% to 10.66% in soils from the five alpine grasslands, with the highest value found in alpine desert and the lowest in alpine meadow. Furthermore, the relative abundance of squalene in alpine grassland soils was significantly negatively associated with soil chemical/microbial characteristics. These results indicate that the extreme environmental conditions of the Tibetan Plateau may stimulate the microbial biosynthesis of squalene, and the harsher the environment, the higher the relative abundance of soil squalene.
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Pradera , Suelo/química , Escualeno/química , Altitud , China , Radiación , Escualeno/aislamiento & purificación , TibetRESUMEN
Secondary salinisation has become a hot spot internationally due to its adverse effects on freshwater ecosystems. Although its effects on ecosystem patterns has been broadly studied, its potential effect on ecosystem functions, in particular on the functional traits of freshwater organisms, and functional trait recovery are largely unknown. In this study, we conducted a field investigation at 405 sample sites from May 2009 to July 2016 in surface mining-contaminated streams, in order to evaluate the influence of secondary salinisation on macroinvertebrate functional traits and the recovery potential of dominant functional traits. Results of univariate models showed that sensitive, very tolerant, gill-breathers, cutaneous-breathers, shredders, predators and gatherers were the most responsive indicators to enhanced specific conductivity and sulfate loadings with sensitive, gill-breathers, shredders and predators demonstrating a reduction in abundance, whereas cutaneous-breathers and gatherers exhibiting an increase. Complicated relationships among different species indicated that co-exclusions would not occur because all macroinvertebrate taxa exhibited positive correlations. Results of relative recovery potential showed that omnivores and gatherers recovered quickly following improvements in water quality, whereas gill-breathers, pneumostome-breathers, filterers and scrapers would be expected to recover slowly due to their sensitivity to both specific conductivity and sulfate and low drift propensity. Overall, secondary salinisation has posed severely ecological risks to macroinvertebrate functional attributes in surface mining-contaminated streams, and their effects should be considered in future conservation plans.
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Mining activity is an increasingly important stressor for freshwater ecosystems. However, the mechanism on how sulfate-rich mine drainage affects freshwater ecosystems is largely unknown, and its potential ecological risk has not been assessed so far. During 2009-2016, water and macroinvertebrate samples from 405 sample sites were collected along the mine drainage gradient from circum-neutral to alkaline waters in Hun-Tai River, Northeastern China. Results of linear regressions showed that sulfate-rich mine drainage was significantly positively correlated with the constituents typically derived from rock weathering (Ca2+, Mg2+ and HCO3-+CO32-); the diversity of intolerant stream macroinvertebrates exhibited a steep decline along the gradient of sulfate-rich mine drainage. Meanwhile, stressor-response relationships between sulfate-rich mine drainage and macroinvertebrate communities were explored by two complementary statistical approaches in tandem (Threshold Indicator Taxa Analysis and the field-based method developed by USEPA). Results revealed that once stream sulfate concentrations in mine drainage exceeded 35mg/L, significant decline in the abundance of intolerant macroinvertebrate taxa occurred. An assessment of ecological risk posed by sulfate-rich mine drainage was conducted based on a tiered approach consisting of simple deterministic method (Hazard Quotient, HQ) to probabilistic method (Joint Probability Curve, JPC). Results indicated that sulfate-rich mine drainage posed a potential risk, and 64.62-84.88% of surface waters in Hun-Tai River exist serious risk while 5% threshold (HC05) and 1% threshold (HC01) were set up to protect macroinvertebrates, respectively. This study provided us a better understanding on the impacts of sulfate-rich mine drainage on freshwater ecosystems, and it would be helpful for future catchment management to protect streams from mining activity.
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Ecosistema , Minería , Ríos/química , Sulfatos/efectos adversos , Contaminantes Químicos del Agua/efectos adversos , Animales , China , Monitoreo del Ambiente , InvertebradosRESUMEN
Specific conductivity is an increasingly important stressor for freshwater ecosystems. Interacting with other environmental factors, it may lead to habitat degradation and biodiversity loss. However, it is still poorly understood how the effect of specific conductivity on freshwater organisms is confounded by other environmental factors. In this study, a weight-of-evidence method was applied to evaluate the potential environmental factors that may confound the effect of specific conductivity on macroinvertebrate structure communities and identify the confounders affecting deriving conductivity benchmark in Hun-Tai River Basin, China. A total of seven potential environmental factors were assessed by six types of evidence (i.e., correlation of cause and confounder, correlation of effect and confounder, the contingency of high level cause and confounder, the removal of confounder, levels of confounder known to cause effects, and multivariate statistics for confounding). Results showed that effects of dissolved oxygen (DO), fecal coliform, habitat score, total phosphorus (TP), pH, and temperature on the relationship between sensitive genera loss and specific conductivity were minimal and manageable. NH3-N was identified as a confounder affecting deriving conductivity benchmark for macroinvertebrate. The potential confounding by high NH3-N was minimized by removing sites with NH3-N > 2.0 mg/L from the data set. Our study tailored the weighting method previously developed by USEPA to use field data to develop causal relationships for basin-scale applications and may provide useful information for pollution remediation and natural resource management.
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Monitoreo del Ambiente/métodos , Nitrógeno/análisis , Ríos/química , Organismos Acuáticos , Biodiversidad , China , Conservación de los Recursos Naturales , Ecosistema , Heces , Concentración de Iones de Hidrógeno , Fósforo/análisis , Temperatura , Microbiología del AguaRESUMEN
The pollution and ecological risk characteristics of five typical antibiotics found in the surface water of the Liaohe River Basin (LRB) were analyzed and evaluated using solid-phase extraction and high-performance liquid chromatography tandem mass spectrometry. These results showed that macrolides have the highest average concentration of all antibiotics in the surface water of the LRB of 201.88 ng·L-1, followed by quinolones, trimethoprim, and sulfonamides with average concentrations of 113.40 ng·L-1, 93.93 ng·L-1, and 124.27 ng·L-1, respectively. Tetracycline demonstrated the lowest concentration at 24.37 ng·L-1. In addition, antibiotics pollution of the Daliao River is clearly identified as being higher than that of the Liaohe River, and the highest proportion of antibiotic pollution (49.1%) is found to come from human use according to a source apportionme0nt analysis. Relatively high levels of ecological risk are identified from Trimethoprim and Erythromycin-H2O concentrations, especially for cities such as Xinmin, Shenyang, and Anshan. The risk assessment indicates that surface water of the LRB faces high ecological risk and argues for greater attention to be paid to risk management and pollution controls.
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Antibacterianos/análisis , Monitoreo del Ambiente , Ríos/química , Contaminantes Químicos del Agua/análisis , China , Cromatografía Líquida de Alta Presión , Ciudades , Medición de Riesgo , Extracción en Fase Sólida , Espectrometría de Masas en TándemRESUMEN
By the method of index evaluation at reach scale, this paper evaluated the ecological functions of aquatic biodiversity maintenance, habitat maintenance, water quality sustainment, and hydrological support of the river system in Taizi River basin of North China. The dominant ecological functions and the total ecological function were determined after sorting and summing. All the reaches in the basin were divided into four hierarchies of ecological functions. Overall, the total ecological function showed a spatially degrading trend from the mountainous region to the plain. Based on the evaluation results of the total function and dominant functions, six ecosystem management strategies were proposed. For the reaches with the functions of aquatic biodiversity- and habitat maintenance, the primary ecological management strategies included ecological conservation, ecological maintenance, and ecological restoration; for the reaches with the functions of water quality sustainment and hydrological support, the primary strategies of ecological management included limited development, development optimization, and exploitation.
Asunto(s)
Acuicultura/métodos , Organismos Acuáticos/clasificación , Biodiversidad , Ecología/métodos , Ecosistema , Ríos , Animales , China , Ecología/organización & administraciónRESUMEN
OBJECTIVE: To provide an understanding of Chinese new mothers' breastfeeding behaviors and especially to explore the relationship between the mothers perceived family perception about breastfeeding and the new mothers' breastfeeding behaviors. STUDY DESIGN: A cross-sectional questionnaire survey was conducted in Beijing and Yinchuan, the capital of Ning Xia Province, China. 214 new mothers with a baby at the age of 4 months were recruited to the study. The family perception of breastfeeding scale and the new mothers' breastfeeding behavior record were used. RESULTS: The response rate was n=200, 94%. Most of the new mothers perceived positive family perceptions about breastfeeding with an average score of 23.13 using the family perception of breastfeeding scale. Nearly half of the respondents reported that they exclusively breastfed their infants (n=94, 47%). The main reason for breastfeeding difficulty was inadequate lactation (n=56, 69%). The new mothers who breastfed their infants mentioned significantly stronger family perceptions/support compared to those who used mixed feeding or artificial feeding (p<0.001). There were no significant differences (p>0.05) in the types of mothers' feeding behaviors across the different age group, occupation, ethnicity, educational level, mode of delivery, the time of the baby's first suck, bottle feeding before the baby's first suck and the time of having colostrums. CONCLUSION: It is suggested to develop some strategies, such as family-centered antenatal and postnatal education programmes, to increase the rate of exclusive breastfeeding by influencing new mothers' families about breastfeeding. Further research is needed to explore socio-demographic variables associated with new-mothers' breastfeeding behaviors.