ABSTRACT
Clarifying the effects of biodiversity on ecosystem stability in the context of global environmental change is crucial for maintaining ecosystem functions and services. Asynchronous changes between trophic levels over time (i.e. trophic community asynchrony) are expected to increase trophic mismatch and alter trophic interactions, which may consequently alter ecosystem stability. However, previous studies have often highlighted the stabilising mechanism of population asynchrony within a single trophic level, while rarely examining the mechanism of trophic community asynchrony between consumers and their food resources. In this study, we analysed the effects of population asynchrony within and between trophic levels on community stability under the disturbances of climate warming, fishery decline and de-eutrophication, based on an 18-year monthly monitoring dataset of 137 phytoplankton and 91 zooplankton in a subtropical lake. Our results showed that species diversity promoted community stability mainly by increasing population asynchrony both for phytoplankton and zooplankton. Trophic community asynchrony had a significant negative effect on zooplankton community stability rather than that of phytoplankton, which supports the match-mismatch hypothesis that trophic mismatch has negative effects on consumers. Furthermore, the results of the structural equation models showed that warming and top-down effects may simultaneously alter community stability through population dynamics processes within and between trophic levels, whereas nutrients act on community stability mainly through the processes within trophic levels. Moreover, we found that rising water temperature decreased trophic community asynchrony, which may challenge the prevailing idea that climate warming increases the trophic mismatch between primary producers and consumers. Overall, our study provides the first evidence that population and trophic community asynchrony have contrasting effects on consumer community stability, which offers a valuable insight for addressing global environmental change.
Subject(s)
Food Chain , Lakes , Phytoplankton , Population Dynamics , Zooplankton , Zooplankton/physiology , Phytoplankton/physiology , Animals , Biodiversity , Climate Change , China , FisheriesABSTRACT
OBJECTIVES: Previous studies have reported satisfactory long-term results of mitral valve (MV) repair for rheumatic mitral disease. However, the effects of this procedure in isolated rheumatic mitral stenosis remain unclear. In addition, protective effects of MV repair on cardiac function have not been verified in rheumatic MV disease. This study retrospectively evaluated early mortality and mid-term results of MV repair for isolated rheumatic mitral stenosis in a mid-volume cardiac centre, and explored the effects of this procedure on cardiac function. METHODS: Between January 2015 and May 2021, 360 patients with isolated rheumatic mitral stenosis and combined (concomitant) atrial fibrillation (AF) underwent MV repair (100 patients) or MV replacement (260 patients). Perioperative characteristics were compared between the two groups and a regression analysis for early mortality and mid-term left ventricular ejection fraction was conducted. In addition, mid-term survival was compared between the two groups. RESULTS: Baseline characteristics of the two groups were balanced after matching. Compared with patients in the replacement group, patients with MV repair had a lower occurrence of postoperative hypotension and AF. There was no difference in early mortality or mid-term survival between the two groups. However, MV repair was associated with a higher mid-term left ventricular ejection fraction. During follow-up, four thromboembolic events and four haemorrhagic events occurred in the replacement group. No blood coagulation-related complications occurred in the repair group. CONCLUSION: Mitral valve repair for isolated rheumatic mitral stenosis and concomitant AF was feasible in a mid-volume cardiac centre, with satisfactory perioperative results and mid-term outcomes. Furthermore, this procedure preserved mid-term left ventricular systolic function.
Subject(s)
Atrial Fibrillation , Heart Valve Prosthesis Implantation , Mitral Valve Insufficiency , Mitral Valve Stenosis , Rheumatic Heart Disease , Humans , Mitral Valve Stenosis/surgery , Retrospective Studies , Stroke Volume , Heart Valve Prosthesis Implantation/methods , Treatment Outcome , Ventricular Function, Left , Rheumatic Heart Disease/complications , Rheumatic Heart Disease/surgery , Mitral Valve Insufficiency/surgeryABSTRACT
Baicalin (BC)-rare earth metal complexes [BMCs (BC-Ce, BC-La, and BC-Y)] were synthesized by a complexation coordination method. A mouse tumor model with SMMC-7721 cells was used to examine BMCs for their anti-tumor activities in vivo. The results show that the three new BMCs, Na3Ce (C21H16O11)3·10H2O, Na2La (C21H16O11)2·8H2O, and Na2Y (C21H16O11)2·6H2O significantly inhibited SMMC-7721 cell proliferation, since the BMCs may induce the tumor apoptosis in a dose-dependent manner through decreasing cell membrane fluidity and mitochondrial membrane potential depolarization, blocking of the cell cycle at the G2/M phase, and increasing the expression of Bax and reducing the expression of Bcl-2. The effectiveness order of these three BCMs was as follows: BC-Ce > BC-La > BC-Y > BC. It is concluded that BC-Ce, BC-La, and BC-Y possess potent anti-tumor effects and may be a novel group of anti-tumor drugs. The novel baicalin-rare earth metal complexes (BMC) were synthesized, the anti-tumor effects of the BMC on SMMC-7721 cell analyzed comprehensively.
Subject(s)
Antineoplastic Agents/pharmacology , Flavonoids/pharmacology , Liver Neoplasms/drug therapy , Metals, Rare Earth/chemistry , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Flavonoids/chemistry , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Membrane Potential, Mitochondrial/drug effects , Metals, Rare Earth/pharmacology , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Synthetic Drugs/chemistry , Synthetic Drugs/pharmacology , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolismABSTRACT
Thoughts of death substantially influence human behavior and psychological well-being. A large number of behavioral studies have shown evidence that asking individuals to think about death or mortality salience leads to significant changes of their behaviors. These findings support the well-known terror management theory to account for the psychological mechanisms of existential anxiety. However, despite increasing findings of mortality salience effects on human behavior, how the brain responds to reminders of mortality and changes the activity underlying subsequent behavior remains poorly understood. By scanning healthy adults (Nâ¯=â¯80) of both sexes using functional magnetic resonance imaging, we showed that, relative to reading emotionally neutral sentences, reading sentences that evoke death-related thoughts decreased the salience network activity, reduced the connectivity between the cingulate cortex and other brain regions during a subsequent resting state, and dampened the speed of learning reward-related objects and cingulate responses to loss feedback during a subsequent reward learning task. In addition, the decreased resting-state cingulate connectivity mediated the association between salience network deactivations in response to reminders of mortality and suppressed cingulate responses to loss feedback. Finally, the suppressed cingulate responses to loss feedback further predicted the dampened speed of reward learning. Our findings demonstrate sequential modulations of the salience network activity by mortality salience, which provide a neural basis for understanding human behavior under mortality threat.
Subject(s)
Attitude to Death , Brain/physiology , Learning/physiology , Nerve Net/physiology , Emotions/physiology , Female , Humans , Magnetic Resonance Imaging , Male , Reward , Young AdultABSTRACT
Bilinguals have been shown to be less susceptible to Stroop interference in their first language than monolinguals, though the cause is currently being debated. In two experiments, we explored how cognitive control and word recognition contribute to the Stroop effect by contrasting cognitive control (via a Simon arrow task), word recognition speed (via a Chinese/English word recognition task) and Stroop susceptibility (via a verbal Stroop task) between proficient and non-proficient Chinese-English bilinguals. Compared to non-proficient bilinguals, proficient bilinguals showed better cognitive control at inhibiting irrelevant information, and they were slower at recognising Chinese words but quicker at recognising English words. Critically, we also showed that proficient bilinguals showed a smaller Stroop effect than non-proficient bilinguals in Chinese but a comparable Stroop effect as non-proficient bilinguals in English. The results cannot be accounted for by cognitive control or word recognition speed alone; instead, they are best accommodated by assuming that cognitive control and word recognition speed jointly determine the Stroop effect. Thus, we conclude that enhanced cognitive control and delayed word recognition combine to reduce Stroop effect in bilinguals as compared to monolinguals.
Subject(s)
Cognition , Multilingualism , Stroop Test , Humans , Language , Male , Task Performance and AnalysisABSTRACT
Introduction: The perceived social support individuals receive from their others plays a crucial role in shaping conformity with social norms. However, the specific mechanism underlying perceived social support and the detection of social norms remains unclear. Methods: In this study, college students with high and low levels of perceived social support were asked to judge the appropriateness of stranger's behaviors (e.g., singing) in different situations (e.g., library). The participants' electroencephalography activities were analyzed aiming to uncover the neural mechanism underlying how perceived social support influences the detection of others' normative behavior. Results: The ERP results indicate that, for individuals with a lower level of perceived social support, larger amplitudes of the N1 component (related to primary processing) and the N400 component (related to cognitive conflict) were observed when detecting others' social norm violation compared to the conformity condition. However, for individuals with a higher level of perceived social support, no significant differences were found in detecting others' conformity or violation of social norms. Discussion: The results indicate that, when the perceived social support level of the individual is low, detecting others' social norm violation elicits deeper primary processing and stronger cognitive conflict compared to conformity condition.
ABSTRACT
Among the problems caused by water eutrophication, the issue of odor compounds has attracted notable attention. ß-Cyclocitral, a widely distributed and versatile odor compound, is commonly derived from both algae and aquatic plants. Planting aquatic plants is a common method of water purification. However, there is limited study on their impact on ß-cyclocitral levels in water. Here, we conducted a study on the ß-cyclocitral levels in water and the submerged plant leaves under three nutrient levels and six plant density treatments. Our findings revealed the following: (1) Chlorophyll-a (Chla), ß-cyclocitral in the water (Wcyc), ß-cyclocitral in Potamogeton lucens leaves (Pcyc) and the biomass of the submerged plants increase with rising nutrient concentration, which increased about 83 %, 95 %, 450 %, 320 % from eutrophic treatment to oligotrophic treatment, respectively. (2) In water, ß-cyclocitral is influenced not only by algae but also by submerged plants, with primary influencing factors varying across different nutrient levels and plant densities. The main source of ß-cyclocitral in water becomes from plants to algae as the water eutrophication and plant density decrease. (3) As submerged plants have the capability to emit ß-cyclocitral, the release of ß-cyclocitral increases with the density of submerged plants. Hence, when considering planting submerged plants for water purification purposes, it is crucial to carefully manage submerged plant density to mitigate the risk of odor pollution emanating from aquatic plants. This study offers fresh insights into selecting optimal water density for submerged plants and their role in mitigating the release of ß-cyclocitral.
Subject(s)
Eutrophication , Odorants , Water Pollutants, Chemical , Odorants/analysis , Water Pollutants, Chemical/analysis , Aldehydes/analysis , Plants , Nutrients/analysis , Environmental Monitoring , DiterpenesABSTRACT
The niobium oxide dihalides have recently been identified as a new class of van der Waals materials exhibiting exceptionally large second-order nonlinear optical responses and robust in-plane ferroelectricity. In contrast to second-order nonlinear processes, third-order optical nonlinearities can arise irrespective of whether a crystal lattice is centrosymmetric. Here, we report third harmonic generation (THG) in two-dimensional (2D) transition metal oxide iodides, namely NbOI2 and TaOI2. We observe a comparable THG intensity from both materials. By benchmarking against THG from monolayer WS2, we deduce that the third-order susceptibility is approximately on the same order. THG resonances are revealed at different excitation wavelengths, likely due to enhancement by excitonic states and band edge resonances. The THG intensity increases for material thicknesses up to 30 nm, owing to weak interlayer coupling. After this threshold, it shows saturation or a decrease, due to optical interference effects. Our results establish niobium and tantalum oxide iodides as promising 2D materials for third-order nonlinear optics, with intrinsic in-plane ferroelectricity and thickness-tunable nonlinear efficiency.
ABSTRACT
An astonishing cultural phenomenon is where, far away from or close to a city center, people in different societies localize cemeteries that function as both sites of memory of lost ones and symbols of mortality. Yet a psychological account of such differences in behavioral responses to symbols of mortality is lacking. Across five studies (N = 1,590), we tested a psychological model that religious afterlife beliefs decrease behavioral avoidance of symbols of mortality (BASM) by developing and validating a word-position task for quantifying BASM. We showed evidence that religious believers, including Christians, Muslims, Hindus, and Buddhists, exhibited decreased BASM relative to nonbelievers. We also provide evidence for a causal relationship between religious afterlife beliefs and reduced BASM. Our findings provide new insight into the functional role of religious afterlife beliefs in modulating human avoidance behavior in response to symbols of mortality.
Subject(s)
Attitude to Death , Buddhism , Christianity , Hinduism , Islam , Religion and Psychology , Symbolism , Adult , Female , Humans , Male , Young Adult , Avoidance Learning , Buddhism/psychology , Cemeteries/statistics & numerical data , China/ethnology , Christianity/psychology , Cities/statistics & numerical data , Culture , Europe/ethnology , Hinduism/psychology , Islam/psychology , Models, Psychological , Self Concept , East Asian People/psychologyABSTRACT
The current study explored the mechanism of self-concealment on perceived social support among youth living alone and tried to clarify the two mediating variables, which are "psychological needs met through internet gratification" and "social self-esteem", by using the Self-Concealment Scale, the Psychological Needs met through Internet Gratification Scale, the Texas Social Behavior Inventory and the Perceived Social Support Scale. Four hundred thirty-three working youth living alone who have lived alone or shared no emotional intersection with others were chosen as participants in this study. The results showed that: (1) the correlation between self-concealment, perceived social support, psychological needs met via internet gratification and social self-esteem was significant; (2) self-concealment positively predicted perceived social support; (3) self-concealment indirectly predicted perceived social support through the chain mediating effect of "psychological needs met via internet gratification" and "social self-esteem". These results indicated that the self-concealment of youth living alone had a predictive effect on the perceived social support. The mechanisms of this effect included the direct effect of self-concealment and indirect effect through "psychological needs met via internet gratification" and "social self-esteem".
Subject(s)
Home Environment , Social Support , Adolescent , Humans , Loneliness , Self Concept , Social Behavior , ChinaABSTRACT
Pancreatic cancer (PC) is a malignant tumour of the human digestive system that has a poor prognosis. Exosomes contain proteins and nucleic acids, and constitute a class of extracellular vesicles defined as membrane-bound nanovesicles of endocytic origin, with a diameter of 40-150 nm. Exosomes are potential diagnostic markers of PC; however, their roles in cancer initiation and progression remain unclear. Previous studies have focused on the molecular mechanisms and functions of exosomes that allow them to accelerate PC cell proliferation, migration and invasion. The present review discusses the interactions between exosomes and the pathophysiology of PC. The potential clinical applications of exosomes are also discussed.
ABSTRACT
Chlorinated phosphorus flame retardants are organic pollutants widely distributed in the environment. However, there is still a lack of understanding of the toxicity mechanism of chlorinated phosphorus flame retardants at the molecular level. Tris (1, 3-dichloroisopropyl) phosphate (TDCPP), tris (2-chloropropyl) phosphate (TCPP) and tris (2-chloroethyl) phosphate (TCEP) were used as typical representatives of chlorinated phosphorus flame retardants to evaluate their cytotoxicity as well as changes in the expression of the enzymes lactate dehydrogenase (LDH), superoxide dismutase (SOD), and catalase (CAT), which will be meaningful for an in-depth study of the toxicity mechanism of TDCPP, TCPP and TCEP. The results showed that the three chemicals reduced cell viability over a period of 24 h. The exposure increased extracellular levels of lactate dehydrogenase and decreased intracellular levels of superoxide dismutase and catalase in a concentration-dependent manner. Expression of the SOD and CAT genes were down-regulated indicating that the SMMC-7721 human hepatocarcinoma cells may experience oxidative damage as a result of exposure to the three chemicals. The expression of the Bax apoptosis protein was up-regulated and the Bcl-2 apoptosis protein was down-regulated, suggesting that the three chemicals may cause functional defects, damage the cell structure and promote apoptosis. The results from this study should provide the basis for a detailed investigation of the ecological toxicity of chlorinated phosphorus flame retardants.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Cell Line, Tumor , Flame Retardants , Humans , Organophosphates , Organophosphorus Compounds , Oxidative Stress , PhosphorusABSTRACT
Filial piety (FP) was formerly a Confucian concept that specifies how children should treat their elders. In recent years, some psychologists have postulated that there are considerable overlaps between Chinese FP and notions found in other cultures. They have redefined FP as a contextualized personality emphasizing the psychological schema of parent-child interaction so that it fits universal cultural contexts. Based on this theory construction, this study aimed to examine the effects of reciprocal FP and authoritarian FP on life satisfaction and the mediating roles of individuating autonomy and relating autonomy therein. To do so, we recruited and surveyed 360 high school students in China. Subsequently, a mediation model based on the Dual Filial Piety Model and previous studies was tested. Results demonstrate that reciprocal FP predicted life satisfaction positively and that both individuating autonomy and relating autonomy played significant mediating roles in the relationship between reciprocal FP and life satisfaction. Moreover, authoritarian FP had a negative indirect effect on satisfaction through the mediating role of individuating autonomy, while authoritarian FP had a positive indirect influence on satisfaction through the mediating role of relating autonomy. The theoretical and practical implications of these findings are discussed.
ABSTRACT
OBJECTIVE: To study the effects of Pim-3 on lung adenocarcinoma A549 cells. A549 cells were divided into an untreated group (without any treatment), a scramble siRNA group (transfected with control siRNA), and a Pim-3-deficient group (transfected with Pim-3 siRNA). METHODS: Pim-3-deficient cells are the experimental sample, whereas scramble siRNA and untreated cells are the corresponding negative controls. Western blotting was performed to detect the expression levels of Pim-3 protein, the phosphorylation of signal transducer and activator of transcription 3 (STAT3), and the expression levels of downstream target genes (p21, cyclin D1, Bcl-2, and Bax). Flow cytometry was performed to analyze cell cycle and apoptosis. RESULTS: In the Pim-3-deficient group, Pim-3 was downregulated, the STAT3 phosphorylation level decreased, the levels of cyclin D1 and Bcl-2 decreased, but the levels of p21 and Bax increased. Meanwhile, cell proliferation was significantly inhibited (P<0.05); specifically, the G0/G1-phase cell proportion increased, whereas the S-phase cell proportion decreased and the proportion of early apoptotic cells increased significantly (P<0.05). CONCLUSION: The downregulation of Pim-3 was closely related to the activation status of the lung STAT3 signaling pathway, mediated cell proliferation inhibition and induced apoptosis.
Subject(s)
Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , STAT3 Transcription Factor/metabolism , A549 Cells , Adenocarcinoma of Lung/metabolism , Adenocarcinoma of Lung/pathology , Apoptosis/genetics , Cell Cycle/genetics , Cell Proliferation/genetics , Down-Regulation , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , PhosphorylationABSTRACT
OBJECTIVE: The present study aims to investigate microRNAs (miRNAs) and messenger RNAs (mRNAs) associated with breast cancer, and to have a better understanding of the mechanism of miRNAs in breast cancer using bioinformatics tools. METHODS: Microarray analysis was performed to predict differentially expressed miRNAs related to breast cancer, followed by prediction and verification of target genes. Human breast cancer cells were transfected and divided into Blank group, NC group, miR-21-5p mimic group, miR-21-5p inhibitor group and siRNA-MAPK10 group. RT-qPCR and Western blot analysis were used to detect mRNA and protein expressions of MAPK10 in tissues and transfected cells, MTT assay, scratch test and Transwell assay for detection of the proliferation, migration and invasion, and Annexin-V-R-PE assay for apoptosis of different cell lines. RESULTS: Highly expressed miR-21-5p and lowly expressed MAPK10 were selected for subsequent experiments, according to the microarray analysis. RT-qPCR showed that the expression of MAPK10 in breast cancer tissues was significantly lower than that in adjacent tissues, while it was reciprocal in expression of miR-21. miR-21-5p negatively regulated MAPK10. The expression of MAPK10 reduced in response to miR-21-5p mimic treatment. Compared with the Blank and NC groups, the proliferation, migration, invasion and metastasis of breast cancer cells decreased, and the apoptosis of breast cancer cells increased in the miR-21-5p inhibitor group and siRNA-MAPK10 group, while it was reciprocal in the miR-21-5p mimic group. CONCLUSION: MiR-21 promotes the proliferation, migration and invasion and inhibits the apoptosis of breast cancer cells by inhibiting MAPK10.
ABSTRACT
Recent behavioral research has shown evidence for greater inclination to avoid symbolic cues of mortality threats in nonbelievers than Christians. However, the neurocognitive mechanisms underlying religious influences on behavioral tendency to avoid mortality threats remain unknown. We tested the hypothesis of distinct arousal/attention-related brain responses to self-related information under mortality in nonbelievers and Christians. We recorded event-related brain potentials (ERPs) from Christians and nonbelievers while they viewed their own names and a stranger's name (i.e., Zuma) that flashed around a cue word (i.e., death, pain or life) located at the center of a screen. While own name vs. a stranger's name induced faster responses and larger P3 amplitudes, the P3 amplitudes to own name showed distinct patterns of modulations by the cue words in nonbelievers and Christians. Specifically, own name elicited larger P3 amplitudes in the death than pain/life cue conditions in nonbelievers but not in Christians. Moreover, the differential P3 amplitude to own names in the death vs. life cue conditions predicted greater inclination to avoid mortality threats in nonbelievers but not in Christians. Our findings provide a neurocognitive account of increased behavioral tendency to avoid mortality threats in nonbelievers than in Christians.