Library size confounds biology in spatial transcriptomics data.

Spatial molecular data has transformed the study of disease microenvironments, though, larger datasets pose an analytics challenge prompting the direct adoption of single-cell RNA-sequencing tools including normalization methods. Here, we demonstrate that library size is associated with tissue structure and that normalizing these effects out using commonly applied scRNA-seq normalization methods will negatively affect spatial domain identification. Spatial data should not be specifically corrected for library size prior to analysis, and algorithms designed for scRNA-seq data should be adopted with caution.

Detection of circulating plasma cells in peripheral blood using deep learning-based morphological analysis.

BACKGROUND: The presence of circulating plasma cells (CPCs) is an important laboratory indicator for the diagnosis, staging, risk stratification, and progression monitoring of multiple myeloma (MM). Early detection of CPCs in the peripheral blood (PB) followed by timely interventions can significantly improve MM prognosis and delay its progression. Although the conventional cell morphology examination remains the predominant method for CPC detection because of accessibility, its sensitivity and reproducibility are limited by technician expertise and cell quantity constraints. This study aims to develop an artificial intelligence (AI)-based automated system for a more sensitive and efficient CPC morphology detection. METHODS: A total of 137 bone marrow smears and 72 PB smears from patients with at Zhongshan Hospital, Fudan University, were retrospectively reviewed. Using an AI-powered digital pathology platform, Morphogo, 305,019 cell images were collected for training. Morphogo's efficacy in CPC detection was evaluated with additional 184 PB smears (94 from patients with MM and 90 from those with other hematological malignancies) and compared with manual microscopy. RESULTS: Morphogo achieved 99.64% accuracy, 89.03% sensitivity, and 99.68% specificity in classifying CPCs. At a 0.60 threshold, Morphogo achieved a sensitivity of 96.15%, which was approximately twice that of manual microscopy, with a specificity of 78.03%. Patients with CPCs detected by AI scanning had a significantly shorter median progression-free survival compared with those without CPC detection (18 months vs. 34 months, p< .01). CONCLUSIONS: Morphogo is a highly sensitive system for the automated detection of CPCs, with potential applications in initial screening, prognosis prediction, and posttreatment monitoring for MM patients. PLAIN LANGUAGE SUMMARY: Diagnosing and monitoring multiple myeloma (MM), a type of blood cancer, requires identifying and quantifying specific cells called circulating plasma cells (CPCs) in the blood. The conventional method for detecting CPCs is manual microscopic examination, which is time-consuming and lacks sensitivity. This study introduces a highly sensitive CPC detection method using an artificial intelligence-based system, Morphogo. It demonstrated remarkable sensitivity and accuracy, surpassing conventional microscopy. This advanced approach suggests that early and accurate CPC detection is achievable by morphology examination, making efficient CPC screening more accessible for patients with MM. This innovative system has the potential to be used in the diagnosis and risk assessment of MM.

Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study.

PURPOSE: The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity (PA) with the risk of incident type 2 diabetes in a population-based prospective cohort study. METHODS: Altogether, 88,000 participants (mean age = 62.2 ± 7.9 years, mean ± SD) were included from the UK Biobank. Sleep duration (short: <6 h/day; normal: 6-8 h/day; long: >8 h/day) and PA of different intensities were measured using a wrist-worn accelerometer over a 7-day period between 2013 and 2015. PA was classified according to the median or World Health Organization-recommendation: total volume of PA (high, low), moderate-to-vigorous PA (MVPA) (recommended, not recommended), and light-intensity PA (high, low). Incidence of type 2 diabetes was ascertained using hospital records or death registries. RESULTS: During a median follow-up of 7.0 years, 1615 incident type 2 diabetes cases were documented. Compared with normal sleep duration, short (hazard ratio (HR) = 1.21, 95% confidence interval (95%CI): 1.03-1.41) but not long sleep duration (HR = 1.01, 95%CI: 0.89-1.15) was associated with excessive type 2 diabetes risk. This increased risk among short sleepers seems to be protected against by PA. Compared with normal sleepers with high or recommended PA, short sleepers with low volume of PA (HR = 1.81, 95%CI: 1.46-2.25), not recommended (below the World Health Organization-recommended level of) MVPA (HR = 1.92, 95%CI: 1.55-2.36), or low light-intensity PA (HR = 1.49, 95%CI: 1.13-1.90) had a higher risk of type 2 diabetes, while short sleepers with a high volume of PA (HR = 1.14, 95%CI: 0.88-1.49), recommended MVPA (HR = 1.02, 95%CI: 0.71-1.48), or high light-intensity PA (HR = 1.14, 95%CI: 0.92-1.41) did not. CONCLUSION: Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes. A higher level of PA, regardless of intensity, potentially ameliorates this excessive risk.

Multifunctional packaging film with sustained release behavior triggered by pH microenvironment for efficient preservation of pork.

To tackle microbial contamination and spoilage during pork storage, transportation, and sales, a novel packaging film with exogenously driven controlled release behavior was designed through the demand-directed preparation of the emulsion of shellac-encapsulated cinnamaldehyde nano-capsules (SNCs) and the ingenious integration of chitosan (CS) film matrix. Among them, the SNCs were synthesized using the solvent exchange method, allowing controlled release of cinnamaldehyde (CA) in response to volatile alkaline substances present in the meat. The electrostatic interaction between SNCs and CS molecules improved the thermal stability, water resistance, tensile strength, and viscosity of the film-forming solution, while the CA in SNCs enhanced UV resistance and antimicrobial properties of the film. Notably, the CS film with SNC-100 loaded (CSNCs-100 film) achieved 99% inhibition against both E. coli and S. aureus, regulated environmental moisture, and prolonged the freshness duration of pork by an impressive six days.

The Joint Effect of Social Comparison and Social Distance on Evaluation of Intertemporal Choice Outcomes in Event-related Potential Studies.

Intertemporal choice plays a crucial role in our daily lives, influencing decisions related to education, health, consumption, and investment. This research proposes an innovative experimental protocol that examines how social comparison and social distance jointly affect the neural processes involved in outcome assessment for intertemporal choices. The study is based on the theoretical framework of cognitive resource competition. This protocol enables researchers to dynamically establish an indifference point for each participant, effectively eliminating the influence of any biased indifference points on the assessment of intertemporal choices. Consequently, the study solely measures the combined impact of social comparison and social distance on how participants evaluate intertemporal choice outcomes. The findings reveal that individuals are more inclined to opt for immediate outcomes under negative unfair conditions. Moreover, compared to the fair and positive unfair conditions, people tend to undervalue delayed outcomes in the negative unfair condition. The strength of this approach lies in its dynamic indifference point setting, making it an effective method to investigate the influence of various external factors (such as social status and power level) on intertemporal decision-making. While the protocol is designed to measure electrophysiological events like event-related potentials, it can also be tailored for use with fMRI.

Predictive Modeling Analysis for the Quality Indicators of Matsutake Mushrooms in Different Transport Environments.

Matsutake mushrooms, known for their high value, present challenges due to their seasonal availability, difficulties in harvesting, and short shelf life, making it crucial to extend their post-harvest preservation period. In this study, we developed three quality predictive models of Matsutake mushrooms using three different methods. The quality changes of Matsutake mushrooms were experimentally analyzed under two cases (case A: Temperature control and sealing measures; case B: Alteration of gas composition) with various parameters including the hardness, color, odor, pH, soluble solids content (SSC), and moisture content (MC) collected as indicators of quality changes throughout the storage period. Prediction models for Matsutake mushroom quality were developed using three different methods based on the collected data: multiple linear regression (MLR), support vector regression (SVR), and an artificial neural network (ANN). The comparative results reveal that the ANN outperforms MLR and SVR as the optimal model for predicting Matsutake mushroom quality indicators. To further enhance the ANN model's performance, optimization techniques such as the Levenberg-Marquardt, Bayesian regularization, and scaled conjugate gradient backpropagation algorithm techniques were employed. The optimized ANN model achieved impressive results, with an R-Square value of 0.988 and an MSE of 0.099 under case A, and an R-Square of 0.981 and an MSE of 0.164 under case B. These findings provide valuable insights for the development of new preservation methods, contributing to the assurance of a high-quality supply of Matsutake mushrooms in the market.

High-accuracy morphological identification of bone marrow cells using deep learning-based Morphogo system.

Accurate identification and classification of bone marrow (BM) nucleated cell morphology are crucial for the diagnosis of hematological diseases. However, the subjective and time-consuming nature of manual identification by pathologists hinders prompt diagnosis and patient treatment. To address this issue, we developed Morphogo, a convolutional neural network-based system for morphological examination. Morphogo was trained using a vast dataset of over 2.8 million BM nucleated cell images. Its performance was evaluated using 508 BM cases that were categorized into five groups based on the degree of morphological abnormalities, comprising a total of 385,207 BM nucleated cells. The results demonstrated Morphogo's ability to identify over 25 different types of BM nucleated cells, achieving a sensitivity of 80.95%, specificity of 99.48%, positive predictive value of 76.49%, negative predictive value of 99.44%, and an overall accuracy of 99.01%. In most groups, Morphogo cell analysis and Pathologists' proofreading showed high intragroup correlation coefficients for granulocytes, erythrocytes, lymphocytes, monocytes, and plasma cells. These findings further validate the practical applicability of the Morphogo system in clinical practice and emphasize its value in assisting pathologists in diagnosing blood disorders.

Joint association of physical activity and sleep duration with risk of all-cause and cause-specific mortality: a population-based cohort study using accelerometry.

AIMS: To investigate the joint association of accelerometer-measured physical activity (PA) and sleep duration with mortality risk. METHODS AND RESULTS: A 7-day accelerometer recording was performed on 92 221 participants (age 62.4 ± 7.8 years; 56.4% women) from the UK Biobank between February 2013 and December 2015. We divided sleep duration into three groups (short, normal, and long), total volume of PA into three levels according to tertiles (high, intermediate, low), and moderate-to-vigorous PA (MVPA) into two groups based on the World Health Organization guidelines. The mortality outcomes were prospectively collected through the death registry. Over a median follow-up of 7.0 years, 3080 adults died, of which 1074 died from cardiovascular disease (CVD) and 1871 from cancer. The associations of PA and sleep duration with mortality risk were all in a curvilinear dose-response pattern (Pnonlinearity <0.001). PA and sleep duration had additive and multiplicative interactions on mortality risk (Pinteraction <0.05). Compared with the participants with guideline-recommended MVPA and normal sleep duration, those without recommended MVPA but having short or long sleep duration were at a higher risk for all-cause mortality [short sleep: hazard ratio (HR) = 1.88; 95% confidence interval (CI), 1.61-2.20; long sleep: HR = 1.69; 95% CI, 1.49-1.90]. A higher volume of PA or recommended MVPA attenuated the detrimental effects of short or long sleep duration on all-cause and CVD mortality risks. CONCLUSION: MVPA meeting recommendations or a higher volume of PA at any intensity potentially diminished the adverse effects on all-cause and cause-specific mortality associated with short and long sleep duration.

All-cause and cause-specific mortality risks associated with accelerometer-measured short or long sleep duration were attenuated by physical activity (PA).Both accelerometer-measured short and long sleep duration were associated with higher risk for all-cause and CVD mortality.Either a higher volume of PA or moderate-to-vigorous PA reaching the WHO-recommended level, as was also measured with accelerometer, attenuated the excessive mortality risks associated with short or long sleep duration.

Microbial ß-glucanases: production, properties, and engineering.

Lignocellulosic biomass, which mainly consists of cellulose and hemicellulose, is the most abundant renewable biopolymer on earth. ß-Glucanases are glycoside hydrolases (GHs) that hydrolyze ß-glucan, one of the dominant components of the plant cell wall, into cello-oligosaccharides and glucose. Among them, endo-ß-1,4-glucanase (EC 3.2.1.4), exo-glucanase/cellobiohydrolase (EC 3.2.1.91), and ß-glucosidase (EC 3.2.1.21) play critical roles in the digestion of glucan-like substrates. ß-Glucanases have attracted considerable interest within the scientific community due to their applications in the feed, food, and textile industries. In the past decade, there has been considerable progress in the discovery, production, and characterization of novel ß-glucanases. Advances in the development of next-generation sequencing techniques, including metagenomics and metatranscriptomics, have unveiled novel ß-glucanases isolated from the gastrointestinal microbiota. The study of ß-glucanases is beneficial for research and development of commercial products. In this study, we review the classification, properties, and engineering of ß-glucanases.

ARBUSCULAR MYCORRHIZA-INDUCED KINASES AMK8 and AMK24 associate with the receptor-like kinase KINASE3 to regulate arbuscular mycorrhizal symbiosis in Lotus japonicus.

Arbuscular mycorrhizal (AM) symbiosis is a widespread, ancient mutualistic association between plants and fungi, and facilitates nutrient uptake into plants. Cell surface receptor-like kinases (RLKs) and receptor-like cytoplasmic kinases (RLCKs) play pivotal roles in transmembrane signaling, while few RLCKs are known to function in AM symbiosis. Here, we show that 27 out of 40 AM-induced kinases (AMKs) are transcriptionally upregulated by key AM transcription factors in Lotus japonicus. Nine AMKs are only conserved in AM-host lineages, among which the SPARK-RLK-encoding gene KINASE3 (KIN3) and the RLCK paralogues AMK8 and AMK24 are required for AM symbiosis. KIN3 expression is directly regulated by the AP2 transcription factor CTTC MOTIF-BINDING TRANSCRIPTION FACTOR1 (CBX1), which regulates the reciprocal exchange of nutrients in AM symbiosis, via the AW-box motif in the KIN3 promoter. Loss of function mutations in KIN3, AMK8, or AMK24 result in reduced mycorrhizal colonization in L. japonicus. AMK8 and AMK24 physically interact with KIN3. KIN3 and AMK24 are active kinases and AMK24 directly phosphorylates KIN3 in vitro. Moreover, CRISPR-Cas9-mediated mutagenesis of OsRLCK171, the sole homolog of AMK8 and AMK24 in rice (Oryza sativa), leads to diminished mycorrhization with stunted arbuscules. Overall, our results reveal a crucial role of the CBX1-driven RLK/RLCK complex in the evolutionarily conserved signaling pathway enabling arbuscule formation.

Integrated metabolomic and transcriptomic analysis reveal the effect of mechanical stress on sugar metabolism in tea leaves (Camellia sinensis) post-harvest.

Sugar metabolites not only act as the key compounds in tea plant response to stress but are also critical for tea quality formation during the post-harvest processing of tea leaves. However, the mechanisms by which sugar metabolites in post-harvest tea leaves respond to mechanical stress are unclear. In this study, we aimed to investigate the effects of mechanical stress on saccharide metabolites and related post-harvest tea genes. Withered (C15) and mechanically-stressed (V15) for 15 min Oolong tea leaves were used for metabolome and transcriptome sequencing analyses. We identified a total of 19 sugar metabolites, most of which increased in C15 and V15. A total of 69 genes related to sugar metabolism were identified using transcriptome analysis, most of which were down-regulated in C15 and V15. To further understand the relationship between the down-regulated genes and sugar metabolites, we analyzed the sucrose and starch, galactose, and glycolysis metabolic pathways, and found that several key genes of invertase (INV), α-amylase (AMY), ß-amylase (BMY), aldose 1-epimerase (AEP), and α-galactosidase (AGAL) were down-regulated. This inhibited the hydrolysis of sugars and might have contributed to the enrichment of galactose and D-mannose in V15. Additionally, galactinol synthase (Gols), raffinose synthase (RS), hexokinase (HXK), 6-phosphofructokinase 1 (PFK-1), and pyruvate kinase (PK) genes were significantly upregulated in V15, promoting the accumulation of D-fructose-6-phosphate (D-Fru-6P), D-glucose-6-phosphate (D-glu-6P), and D-glucose. Transcriptome and metabolome association analysis showed that the glycolysis pathway was enhanced and the hydrolysis rate of sugars related to hemicellulose synthesis slowed in response to mechanical stress. In this study, we explored the role of sugar in the response of post-harvest tea leaves to mechanical stress by analyzing differences in the expression of sugar metabolites and related genes. Our results improve the understanding of post-harvest tea's resistance to mechanical stress and the associated mechanism of sugar metabolism. The resulting treatment may be used to control the quality of Oolong tea.

Associations of timing of physical activity with all-cause and cause-specific mortality in a prospective cohort study.

There is a growing interest in the role of timing of daily behaviors in improving health. However, little is known about the optimal timing of physical activity to maximize health benefits. We perform a cohort study of 92,139 UK Biobank participants with valid accelerometer data and all-cause and cause-specific mortality outcomes, comprising over 7 years of median follow-up (638,825 person-years). Moderate-to-vigorous intensity physical activity (MVPA) at any time of day is associated with lower risks for all-cause, cardiovascular disease, and cancer mortality. In addition, compared with morning group (>50% of daily MVPA during 05:00-11:00), midday-afternoon (11:00-17:00) and mixed MVPA timing groups, but not evening group (17:00-24:00), have lower risks of all-cause and cardiovascular disease mortality. These protective associations are more pronounced among the elderly, males, less physically active participants, or those with preexisting cardiovascular diseases. Here, we show that MVPA timing may have the potential to improve public health.

Validation of a wearable forehead sleep recorder against polysomnography in sleep staging and desaturation events in a clinical sample.

STUDY OBJECTIVES: Wearable sleep recording devices may be a helpful alternative method for polysomnography (PSG) due to their higher accessibility and comfort as well as lower cost, but their validities need to be examined. The aim of this study was to evaluate the accuracy of a novel single-channel, electroencephalography-based wearable forehead sleep recorder (UMindSleep) to assess sleep staging and oxygen desaturation. METHODS: Two hundred and three Chinese adults recruited from a sleep medicine center underwent an overnight study wearing UMindSleep and PSG simultaneously. Sleep parameters including sleep staging and oxygen desaturation index were compared between UMindSleep and PSG. RESULTS: A total of 195,349 valid epochs from 197 participants (171 with obstructive sleep apnea, 86.8%) were included in analyses of sleep staging. Sensitivities of UMindSleep compared to PSG were 79.7% for wake, 85.8% for light sleep, 79.4% for deep sleep, and 82.7% for rapid eye movement sleep. Specificities were 95.3% for wake, 83.4% for light sleep, 97.0% for deep sleep, and 96.8% for rapid eye movement sleep. Furthermore, the kappa agreements of 0.69-0.79 were indicative of a substantial agreement for sleep staging between UMindSleep and PSG. Sensitivity and specificity regarding oxygen desaturation index were 93.4% and 88.9%, yielding a kappa coefficient of 0.82. CONCLUSIONS: Our findings suggest that UMindSleep may serve as a feasible, accurate, and dependable device for screening of sleep disorders (eg, obstructive sleep apnea) and assessing sleep structure. CITATION: Chen X, Jin X, Zhang J, Ho KW, Wei Y, Cheng H. Validation of a wearable forehead sleep recorder against polysomnography in sleep staging and desaturation events in a clinical sample. J Clin Sleep Med. 2023;19(4):711-718.

Human Endogenous Retroviruses and Toll-Like Receptors.

Human endogenous retroviruses (HERVs) are estimated to comprise ∼8% of the entire human genome, but the vast majority of them remain transcriptionally silent in most normal tissues due to accumulated mutations. However, HERVs can be frequently activated and detected in various tissues under certain conditions. Nucleic acids or proteins produced by HERVs can bind to pattern recognition receptors of immune cells or other cells and initiate an innate immune response, which may be involved in some pathogenesis of diseases, especially cancer and autoimmune diseases. In this review, we collect studies of the interaction between HERV elements and Toll-like receptors and attempt to provide an overview of their role in the immunopathological mechanisms of inflammatory and autoimmune diseases.

Seasonal expression of cytoplasmic creatine kinase in the epididymal epithelium of Pelodiscus sinensis.

During hibernation of Pelodiscus sinensis, sperm mature and are stored in the epididymis. We investigated seasonal changes in the morphology of epithelial cells of the epididymis of P. sinensis and changes in expression of cytoplasmic creatine kinase (CK). We found that the epididymal epithelium proliferates rapidly to form multiple layers from June to September, while the epididymal epithelial cells are arranged in a single layer from October to May. From the March before the mating period to the end of the mating period in September, a large amount of neutral glycoprotein is secreted in the epididymal epithelium and in the sperm aggregation area; after October, the glycoprotein in the epididymis decreases. At sperm maturation, cytoplasmic CK is expressed abundantly in the villous epithelium, which is formed by proliferation of epididymal epithelial cells. During hibernation and reproduction, the epididymal epithelium of P. sinensis exhibits different proliferation and secretion patterns as the animal adapts to two types of sperm storage. Cytoplasmic CK may participate in regulating the energy metabolism of the epididymal epithelium; it is an important enzyme for regulating sperm maturation.

Quinoline-cored Poly(Aryl Ether) Dendritic Organogels with Multiple Stimuli-Responsive and Adsorptive Properties.

Functional supramolecular gel materials have potential applications in sensors, optical switches, artificial antennae, drug delivery and so on. In this paper, quinoline-cored poly(aryl ether) dendritic organogelators were designed, synthesized and fully characterized. The gelation behaviour of the dendritic organogelator was tested in organic solvents, mixed solvents and ionic liquids. The dendron Q-G1 was found to be an efficient and versatile organogelator toward various apolar and polar organic solvents with the critical gelation concentrations (CGCs) approaching 1.2×10-2  mol/L, indicating one dendritic organogelator could immobilize 1.2×103 solvent molecules in the organogel network. Interestingly, these dendrons exhibited excellent gel formation in ionic liquids. Notably, these dendritic organogels were found to display multiple stimuli-responsive properties toward external stimuli including heat, ultrasound and shear stress, with a reversible sol-gel phase transition. In addition, the dendritic organogel could effectively adsorb heavy metals and organic dyes. The removal rate of Pb2+ was up to 20% and the adsorption rate for Rhodamine B was as high as 89%.

PbI2-TiO2 Bulk Heterojunctions with Long-Range Ordering for X-ray Detectors.

High-performance X-ray detectors are usually based on single crystals, due to the long-range ordering and hence outstanding electronic properties. On the other hand, bulk heterojunctions (BHJs) that can effectively enhance photogenerated exciton dissociation are widely used for photodetectors. The benefits of both spur investigation into how to combine these two strategies to enhance X-ray detection. Here, TiO2 networks are incorporated into PbI2 crystals to form interpenetrating type II heterojunctions, namely BHJs. These BHJs exhibit long-range ordering in molecular packing similar to that of single crystals. Compared with single crystals, the long-range ordered BHJs facilitate the separation of photogenerated electrons and holes to inhibit recombination, extend the mobility lifetime product by 6.4 times, and consequently improve X-ray sensitivity by 5.8 times. Hence, this work provides a new strategy using gel-grown crystals to fabricate high-performance X-ray detectors as well as a new platform for studying the behavior of X-ray-generated carriers in BHJs with long-range ordering.

Neuroprotective and Anti-Amyloid ß Effect and Main Chemical Profiles of White Tea: Comparison Against Green, Oolong and Black Tea.

White tea (WT) is one of six tea types originally derived from Fujian Province, China. White tea is known for its health-promoting properties. However, the neuroprotective and anti-aggregatory properties of WT against the hallmark toxic Alzheimer's protein, Aß have not been investigated. In this study, WT, green tea (GT), oolong tea (OT) and black tea (BT) were manufactured using tea leaves from the cultivar Camellia sinensis (Jin Guanyin). The protective effects of these tea extracts were then studied under oxidative stress conditions via t-bhp and H2O2 exposure, in addition to Aß treatment using a PC-12 cell model. Each tea type failed to rescue PC-12 cells from either t-bhp or H2O2-mediated toxicity, however each extract exerted significant protection against Aß-evoked neurotoxicity. Results of the Thioflavin T Kinetic (ThT) and TEM assay showed that Aß aggregate formation was inhibited by each tea type. Additionally, TEM also supported the different anti-aggregatory effect of WT by modifying Aß into an amorphous and punctate aggregate morphology. Higher accumulated precedent or potential neuroprotective compounds in WT, including ECG''3Me, 8-C-ascorbyl-EGCG, GABA and Gln, in addition to flavonol or flavone glycosides detected by using UPLC-QTOF-MS and UPLC-QqQ-MS, may contribute to a favourable anti-aggregative and neuroprotective effect of WT against Aß.

How you act matters: The impact of coordination on 4-year-old children's reasoning about diverse desires.

Cooperation is generally found to have a more positive impact than competition on children's high-level social understanding (e.g., diverse desires, false beliefs); however, recent evidence has shown that competition could also improve such understanding. Differences in coordination level during interactions with others may potentially explain these inconsistent results. In this study, we tested the impact of coordination on children's ability to reason about diverse desires in both competitive and cooperative conditions. Four-year-old children played a competitive (Experiment 1, N = 48) or cooperative (Experiment 2, N = 48) game with an adult. They were then tested for their understanding of diverse desires in a gift selection condition that was difficult for children of this age. Coordination levels were manipulated as high versus low in both games. Results showed that coordination enhanced children's performance in reasoning about diverse desires, allowing children to conduct desire inferences and perspective taking simultaneously in both conditions. This finding accords well with the constructivist view that social understanding could be shaped by the underlying structure of the social interaction in which one participates. More important, it adds to our knowledge about how social interaction enhances one's social understanding at an early age; specifically, it highlights the decisive role of coordination in this process.

Cooperation, but not competition, improves 4-year-old children's reasoning about others' diverse desires.

Three experiments examined whether cooperation or competition affects 4-year-old children's reasoning about other people's desires-which differed from their own-in a gift selection task. Experiment 1 (N=72) found that children's performance in selecting an adult-preferred gift for an adult experimenter was enhanced by a short period of preceding cooperative, but not competitive or individualistic, play with the experimenter. Experiment 2 (N=24) ruled out the alternative explanation that children resisted satisfying their opponent after competition. Experiment 3 (N=48) replicated the cooperation advantage in selecting a gift for someone else, indicating that children's understanding of diverse desires was generally improved by cooperation but not competition. These findings support the constructivist view of social development and highlight the advantage of cooperation.