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The ability of solving problems collaboratively has been increasingly significant. This research takes mathematics open-ended problems as the tasks and carries out collaborative problem solving with multi-machine video recording in the classroom environment aimed at 112 student pairs and 56 four-person student groups stemming from 224 students in the seventh grade. Based on the theory of commognition, this research develops an analytical framework for the performance of commognition in students' collaborative problem solving and provides several criteria for the marginalization of commognition. Through visual analysis and representation, the results show that the capacity of group meta-level commognition is lower than that of pairs, the male has better commognitive performance than the female, and group marginalization is more serious than that of pairs.

【Objective】 Precipitation and its variation is the driver of all ecological functions in a catchment. It is affected by many factors. This paper investigates the variation in precipitation and its multi-scale correlations with atmospheric circulation in the Taihu Lake Basin (TLB), China. 【Method】 The analysis was based on precipitation measured from 1960 to 2020 from 30 meteorological stations across the basin. Its multi-scale oscillations, as well as correlation with single and combined atmospheric circulation factors were analyzed using the Mann Kendall (MK), modified Mann Kendall (MMK), wavelet coherence (WTC), and multiple wavelet coherence (MWC). 【Result】 ① The annual and seasonal trends identified by MMK and MK from the precipitation series was similar, but the significance differed between the two methods. We found the largest upward trend in annual precipitation, but the seasonal precipitation in winter had the smallest upward trend. MMK detected significance that MK failed to identify, especially for spring precipitation. ② WTC found that the precipitation and atmospheric circulation factors were nonlinearly correlated in a complex way, but their correlation varied with time. ③ For single atmospheric circulation factors, the EASM was the most influential teleconnection affecting precipitaton in the TLB. Among the multivariates, Prep-AO-PDO-ENSO-EASM-DMI had the greatest impact on precipitation in TLB. 【Conclusion】 The dominant tele-correlation alone cannot explain the relationship between precipitation and atmospheric circulation, and a combination of atmospheric circulation factors and the highest percentage of significant power (POSP) offered the best explanation for precipitation variation in TLB.

Owing to rapid urbanization, the Beijing–Tianjin–Hebei region in China faces considerable urban heat island (UHI) effects, which can be mitigated by blue-green space construction. In this study, we used multi-source remote sensing products and the InVEST model's urban cooling module to analyze the spatiotemporal changes in blue-green space cooling effects from 1990 to 2020. The wavelet coherence theory was used to explore these changes, as well as the environmental factors that affect cooling. The key findings indicate that the cooling effect is closely related to urbanization, as similar trends and significant temporal differences in cooling indices were observed in central urban areas, the urban fringe, and the city center. In addition, climatic factors such as temperature and precipitation substantially influenced cooling, with an average wavelet coherence of 0.88. Seasonal variations in cooling were notable, with temperature exhibiting the best coherence across all time–frequency scales (averaging 0.55). The findings highlight the critical role of blue-green spaces for mitigating UHI effects, which provides scientific insights for urban planning and environmental management. [ABSTRACT FROM AUTHOR]

Objective: We conducted a prospective randomized clinical trial to compare the efficacy of low‐ and high‐dose radioiodine for remnant ablation in patients with low‐risk differentiated thyroid cancer (DTC) in China. The first‐stage results showed equivalence was observed between the two groups. Here, we report recurrence and survival at 3–5 and 6–10 years and biochemical parameters. Design, Patients and Methods: Between January 2013 and December 2014, adult patients with DTC were enroled. Patients had undergone total or near‐total thyroidectomy, with or without cervical lymph node dissection, with tumour stages T1–T3 with or without lymph node metastasis, but without distant metastasis. Patients were randomly assigned to the low‐dose (1850 MBq) or high‐dose (3700 MBq) radioiodine group. They were then followed up for 3–5 and 6–10 years. Data on biochemical abnormalities, recurrence and survival were analysed using Kolmogorov–Smirnov and χ2 tests. Results: The data of 228 patients (mean age = 42 years; 70.6% women) were analysed, with 117 patients in the low‐dose group and 111 in the high‐dose group. There were no significant differences in biochemical abnormalities, recurrence, or survival rates at the 6–10‐year follow‐up (all p >.05). Nine patients experienced recurrence in the low‐dose group (8.7%), while eight patients experienced recurrence in the high‐dose group (8.2%). The survival rates were 100% and 98.2% in the low‐ and high‐dose groups, respectively. Conclusions: The long‐term effectiveness and safety of low‐dose (1850 MBq) radioiodine are the same as those of high‐dose (3700 MBq) radioiodine for thyroid remnant ablation in Chinese patients with low‐risk DTC. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) persistent luminescence nanoparticles (PLNPs) showed great potential for bioimaging due to their integration of non-in situ excitation and deep tissue penetration. However, PLNPs are often introduced with Cr3+ ions as the NIR emission centers. Herein, we report Cr-free Bi2Ga3.985O9:1.5% Fe3+ (BGF), with Fe3+ ions as the NIR emission centers. BGF under 310 nm excitation exhibited NIR afterglow emission at 794 nm in the first biological imaging window (650–950 nm), with the afterglow duration of 3 h. BGF was grafted with hydroxyl groups and then polydopamine (PDA) for the integration of indocyanine green (ICG) through π–π stacking and hydrophobic interactions, as the PLNP–PDA–ICG composite. Bi in the composite, as a heavy atom element, exhibits computed tomography (CT) contrast capacity, while PDA is a photothermal agent, and ICG is excited to produce reactive oxide species for photodynamic therapy. The afterglow/CT dual-modality imaging-guided photothermal/photodynamic combination therapy was validated with in vitro/vivo imaging and therapeutic applications. This work provides the Cr-free PLNP composite for drug-free theranostics with a low toxicity. [ABSTRACT FROM AUTHOR]

In this study, we investigated reversible intermolecular proton shifting (IPS) coupled with spin transition (ST) in a novel FeII complex. The host FeII complex and the guest carboxylic acid anion were connected by intermolecular hydrogen bonds (IHBs). We extended the intramolecular proton transfer coupled ST phenomenon to the intermolecular system. The dynamic phenomenon was confirmed by variable‐temperature single‐crystal X‐ray diffraction, neutron crystallography, and infrared spectroscopy. The mechanism of IPS was further validated using density functional theory calculations. The discovery of IPS‐coupled ST in crystalline molecular materials provides good insights into fundamental processes and promotes the design of novel multifunctional materials with tunable properties for various applications, such as optoelectronics, information storage, and molecular devices. [ABSTRACT FROM AUTHOR]

To achieve indoor thermal comfort via natural ventilation, traditional buildings in South China's Lingnan region have evolved distinct features tailored to the hot and humid climate conditions, involving site planning, function layout, and construction techniques. This study delves into the influences of these features on aspects such as sun-shading, ventilation, and heat insulation. By analyzing over ten Lingnan buildings in both the traditional and modern forms, several representative standardized models have been developed. Through a hybrid approach of combining qualitative and quantitative methodologies, including simulations, quantifications, and comparisons, several passive heat-protection measures commonly employed in Lingnan buildings were examined and evaluated. The effectiveness of shading, ventilation, and heat insulation in both traditional and modern buildings was assessed, resulting in the compilation of design principles for passive heat protection in buildings located in similar climatic zones. Key findings include (1) Shading: traditional methods reduce sunlight by 54.55%, while modern buildings enhance shading by applying new materials; (2) ventilation: traditional design achieves an outdoor wind speed of 1.5 m/s, improving thermal comfort, while modern Lingnan buildings optimize these principles; (3) insulation: traditional techniques maintain indoor temperatures below 26.0 °C, and modern buildings introduce innovation solutions for improved thermal insulation. In summary, traditional Lingnan design effectively addresses the challenges of the hot and humid climate by employing passive strategies for thermal comfort. Modern Lingnan buildings, in turn, preserve these principles while introducing innovative approaches. [ABSTRACT FROM AUTHOR]

Pathological myocardial remodelling is the initial factor of chronic heart failure (CHF) and is induced by multiple factors. We previously demonstrated that histone acetylation is involved in CHF in transverse aortic constriction (TAC) mice, a model for pressure overload‐induced heart failure. In this study, we investigated whether the histone deacetylase Sirtuin 6 (SIRT6), which mediates deacetylation of histone 3 acetylated at lysine 9 (H3K9ac), is involved pathological myocardial remodelling by regulating myocardial energy metabolism and explored the underlying mechanisms. We generated a TAC mouse model by partial thoracic aortic banding. TAC mice were injected with the SIRT6 agonist MDL‐800 at a dose of 65 mg/kg for 8 weeks. At 4, 8 and 12 weeks after TAC, the level of H3K9ac increased gradually, while the expression of SIRT6 and vascular endothelial growth factor A (VEGFA) decreased gradually. MDL‐800 reversed the effects of SIRT6 on H3K9ac in TAC mice and promoted the expression of VEGFA in the hearts of TAC mice. MDL‐800 also attenuated mitochondria damage and improved mitochondrial respiratory function through upregulating SIRT6 in the hearts of TAC mice. These results revealed a novel mechanism in which SIRT6‐mediated H3K9ac level is involved pathological myocardial remodelling in TAC mice through regulating myocardial energy metabolism. These findings may assist in the development of novel methods for preventing and treating pathological myocardial remodelling. [ABSTRACT FROM AUTHOR]

Various types of geofluids exist in deep and ultra-deep layers in petroliferous basins. The geofluids are much more active under high-temperature and high-pressure (HTHP) conditions, but their properties are unclear. We simulated the mixing of different fluids in CH4/C3H8/C6H14/C8H18-water systems and C6H14/C8H18-CO2-H2O systems at temperatures of 25°C to 425°C and pressures of 5 MPa to 105 MPa, using an in-situ micron quartz capillary tube thermal simulation system and molecular dynamics numerical simulation software. The mixing processes, patterns, and mechanisms of various fluids were analyzed at microscale under increasing temperature and pressure conditions. The results show that the miscibility of fluids in the different alkane-H2O and alkane-CO2-H2O systems is not instantaneous, but the miscibility degree between different fluid phases increases as the temperature and pressure rise during the experiments. The physical thermal experiments (PTEs) show that the mixing process can be divided into three stages: initial miscibility, segmented dynamic miscibility, and complete miscibility. The molecular dynamics numerical simulations (MDNSs) indicate that the mixing process of fluids in the alkane-H2O and alkane-CO2-H2O systems can be divided into seven and eight stages, respectively. The carbon number affects the miscibility of alkanes and water, and the temperature and pressure required to reach the same miscibility stage with water increase with the carbon number (C3H8, C6H14, CH4, C8H18). CO2 has a critical bridge role in the miscibility of alkanes and water, and its presence significantly reduces the temperatures required to reach the initial, dynamic, and complete miscibility of alkanes and water. The results are of great significance for analyzing and understanding the miscibility of geofluids in deep and ultra-deep HTHP systems. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the 95% EtOH extract of the Traditional Chinese Medicine (TCM) Euphorbia royleana (Ba-wang-bian in Chinese) led to the isolation of 11 diterpenoids (1–11) and two triterpenoids (12 and 13). Among them, compounds 1 and 2 were new ingenane and ingol diterpenoids, respectively. Their structures were elucidated by a combination of spectroscopic analyses (1 D and 2 D NMR, HRMS, ECD, UV, and IR data) and chemical methods. Compounds 12 and 13 exhibited moderate cytotoxicities in vitro against human lung cancer cell line A549 with IC50 values of 14.84 ± 0.56 and 27.11 ± 1.65 µM, respectively. [ABSTRACT FROM AUTHOR]

The crystallization of a complex having electron transfer properties in a polar space group can induce the polarization switching of a crystal in a specific direction, which is attractive for the development of sensors, memory devices, and capacitors. Unfortunately, the probability of crystallization in a polar space group is usually low. Noticing that enantiopure compounds crystallize in Sohncke space groups, this paper reports a strategy for the molecular design of non‐ferroelectric polarization switching crystals based on the use of intramolecular electron transfer and chirality. In addition, this paper describes the synthesis of a mononuclear valence tautomeric (VT) cobalt complex bearing an enantiopure ligand. The introduction of enantiomer enables the crystallization of the complex in the polar space group (P21). The polarization of the crystals along the b‐axis direction is not canceled out and the VT transition is accompanied by a change in the macroscopic polarization of the polar crystal. Polarization switching via electron transfer is realized at around room temperature. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction to CH4 is a promising strategy for converting the main greenhouse gas CO2 to achieve a future with net-zero emissions. However, efficient photocatalysts with high selectivity are still far from being applied. In the present work, we reported BiOCl nanosheets loaded with noble metals (Au, Ag, Pt, or Pd), fabricated via a facile photodeposition method, for photocatalytic CO2 reduction. Among these metals, Pd-loaded BiOCl (Pd/BiOCl) with 1.0 wt% loading showed the highest activity and best selectivity toward CH4 formation. The enhancements in activity and selectivity were further studied by investigating the photogenerated electron–hole separation efficiency and surface intermediate pathways during photocatalytic CO2 reduction. It was found that Pd-loaded BiOCl could effectively decrease the recombination of electrons and holes and improve the photocurrent density during light irradiation. Furthermore, surface CO2 adsorption studies based on in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) implied that bicarbonates rather than carbonates were the main species on Pd/BiOCl under dark conditions. These species were increased and further transformed to bidentate formate and methoxy as key intermediates during CH4 formation. The enhanced charge separation efficiency and formation of bidentate formate and methoxy on Pd/BiOCl promoted the CH4 activity and selectivity during photocatalytic CO2 reduction. Our work provides a facile and efficient way to achieve photocatalytic CO2 reduction for the selective formation of CH4. [ABSTRACT FROM AUTHOR]

Previously, we have reported that an endo-type β-agarase AgaW was responsible for the hydrolysis of agarose into the major product neoagarotetraose in a terrestrial agar-degrading bacterium Cohnella sp. LGH. Here, we identify and characterize the following depolymerization pathway in strain LGH through the genomic and enzymatic analysis. In the pathway, neoagarotetraose was depolymerized by a novel α-neoagarooligosaccharide (NAOS) hydrolase CL5012 into 3,6-anhydro-α-L-galactose (L-AHG) and agarotriose; Agarotriose was further depolymerized by a novel agarolytic β-galactosidase CL4994 into D-galactose and neoagarobiose; Neoagarobiose was finally depolymerized by CL5012 into L-AHG and D-galactose. Although α-agarase has not been identified in strain LGH, the combined action of CL5012 and CL4994 unexpectedly plays a critical role in the depolymerization of agarotetraose, one theoretical product of α-agarase hydrolysis of agarose. In this pathway, agarotetraose was depolymerized by CL4994 into D-galactose and neoagarotriose; Neoagarotriose was then depolymerized by CL5012 into L-AHG and agarobiose. Furthermore, another novel endo-type β-agarase CL5055 was identified as an isozyme of AgaW with different pH preference in the hydrolysis of agarose into α-NAOSs. Strain LGH seemed to lack a common exo-type β-agarase responsible for the direct depolymerization of agarose or neoagarooligosaccharide into neoagarobiose. These results highlight the diversity of agarolytic manner in bacteria and provide a novel insight on the diversity of agarolytic pathways. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is a complex process induced by the activation of multiple signaling pathways. We previously reported that anacardic acid (AA), a histone acetyltransferase (HAT) inhibitor, attenuates phenylephrine (PE)-induced cardiac hypertrophy by downregulating histone H3 acetylation at lysine 9 (H3K9ac). Unfortunately, the related upstream signaling events remained unknown. The mitogen-activated protein kinase (MAPK) pathway is an important regulator of cardiac hypertrophy. In this study, we explored the role of JNK/MAPK signaling pathway in cardiac hypertrophy induced by PE. The mice cardiomyocyte hypertrophy model was successfully established by treating cells with PE in vitro. This study showed that p-JNK directly interacts with HATs (P300 and P300/CBP-associated factor, PCAF) and alters H3K9ac. In addition, both the JNK inhibitor SP600125 and the HAT inhibitor AA attenuated p-JNK overexpression and H3K9ac hyperacetylation by inhibiting P300 and PCAF during PE-induced cardiomyocyte hypertrophy. Moreover, we demonstrated that both SP600125 and AA attenuate the overexpression of cardiac hypertrophy-related genes (MEF2A, ANP, BNP, and β-MHC), preventing cardiomyocyte hypertrophy and dysfunction. These results revealed a novel mechanism through which AA might protect mice from PE-induced cardiomyocyte hypertrophy. In particular, AA inhibits the effects of JNK signaling on HATs-mediated histone acetylation, and could therefore be used to prevent and treat pathological cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

Iodide uptake and the metabolism of thyroid cells are regulated by thyrotropin (TSH)-TSH receptor (TSHR) signaling. Thus, it is necessary to elevate serum TSH levels by T4 withdraw or rTSH administration to facilitate radioiodide (131I) therapy for differentiated thyroid cancer (DTC). However, non-iodide-avid metastases of DTC which is dedifferentiated do not respond to stimulation by high levels of TSH, suggesting abnormal TSH-TSHR signal transduction in cancer cells. In addition, PI3K/AKT/mTOR signaling activation has been shown to be associated with the dedifferentiated phenotype of thyroid cancer, but the mechanism remains elusive. Therefore, in this study, we aimed to explore the role of abnormal TSH-TSHR signaling activation in regulating iodide uptake and cell mobility in thyroid cancer and its relationship with PI3K/AKT/mTOR signaling. We found that in thyroid cancer cells, TSH binds TSHR coupled to the Gα12/13 protein and then activates RhoA through interacting with leukemia associated RhoA guanine exchange factor (LARG). This results in a promigration tumorigenic phenotype independent of canonical TSHR-GαS signaling that regulates the expression of molecules involved in iodine uptake and metabolism. We observed that signaling pathways downstream of Gα12/13 signaling were increased, while that of Gαs signaling was decreased in thyroid cancer cells undergoing dedifferentiation compared to control cells following stimulation with different levels of TSH. PI3K/AKT/mTOR signaling activation enhanced Gα12/13 signaling through increasing LARG levels but also inhibited the expression of molecules downstream of Gαs signaling, including thyroid-specific molecules, and iodide uptake. In summary, our results demonstrate the noncanonical activation of TSH-TSHR signaling and its role in increasing the cell mobility and dedifferentiation of thyroid cancer through crosstalk with PI3K/AKT/mTOR signaling. [ABSTRACT FROM AUTHOR]

A proton–electron coupling system, exhibiting unique bistability or multistability of the protonated state, is an attractive target for developing new switchable materials based on proton dynamics. Herein, we present an iron(II) hydrazone crystalline compound, which displays the stepwise transition and bistability of proton transfer at the crystal level. These phenomena are realized through the coupling with spin transition. Although the multi‐step transition with hysteresis has been observed in various systems, the corresponding behavior of proton transfer has not been reported in crystalline systems; thus, the described iron(II) complex is the first example. Furthermore, because proton transfer occurs only in one of the two ligands and π electrons redistribute in it, the dipole moment of the iron(II) complexes changes with the proton transfer, wherein the total dipole moment in the crystal was canceled out owing to the antiferroelectric‐like arrangement. [ABSTRACT FROM AUTHOR]

Plant invasion initiates with the establishment of an alien species population that begins interacting with the existing community in the invaded habitat. Competitive ability may confer advantage to invasive species during establishment. Autopolyploidy has been shown to significantly contribute to successful invasion of China by Solidago canadensis that is native to North America. But how polyploidization improves competitive ability and determines the dominance of invasive species when competing with a plant community in the introduced range remains unclear. Here, we manipulated the initial plant composition of plowed land and subsequently allowed natural colonization by S. canadensis in a five‐year common garden experiment. Diploid, tetraploid and hexaploid populations collected in North America (native range) and East Asia (introduced range) were separately planted and allowed to compete with associated weeds in individual plots. The diversity and compositional variation of the plant communities and the growth characteristics of S. canadensis were investigated in summer and autumn each year. Based on how the community assembled, three outcomes were found: 1) S. canadensis outcompeted local vegetation: tetraploids and hexaploids from the introduced range outcompeted associated weeds and were dominant at equilibrium; 2) S. canadensis coexisted with local vegetation: hexaploids from the native range were competitive but ultimately could not outcompete the local vegetation; and 3) S. canadensis became extinct: diploids from both the native and introduced ranges and tetraploids from the native range went extinct. Concomitantly, diversity was low in the first group and high in the second and third. Therefore, polyploidization contributes to the pre differentiation of competitive ability among native S. canadensis populations, facilitatating the invasion of China by this species. The competitive ability of polyploids was enhanced through possible rapid post introduction evolution after their introduction into China, which could be the crucial factor for successful invasion by S. canadensis. [ABSTRACT FROM AUTHOR]

Some cyanide‐bridged complexes are known for exhibiting slow magnetic relaxation behavior in a light‐induced metastable state. Herein, an unexpected reverse effect is observed for the first time in the S=1/2 {FeIILS‐CoIIILS‐FeIIILS} (HS=high spin, LS=low spin) ground state of a novel V‐shaped trinuclear cyanide‐bridged {Fe2Co} complex. In this complex, light‐switchable iron‐cobalt charge transfer with repeatable off/on switching of slow magnetic relaxation is discovered upon alternating laser irradiation at 785 and 560 nm. An important characteristic of the present compound is that the S=1/2 ground state exhibits slow magnetic relaxation before irradiation, whereas this is accelerated after irradiation. This is different from the typical behavior, where the light‐induced metastable state exhibits slow magnetic relaxation. [ABSTRACT FROM AUTHOR]