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The joint inversion of Rayleigh and Love waves plays a crucial role in mitigating the non‐uniqueness of surface wave inversion results and enhancing the stability of these inversions. Existing approaches to the joint inversion of Rayleigh and Love wave dispersion curves, which rely on conventional objective functions, often struggle with complex stratigraphic configurations and yield results of limited accuracy. This study introduces two novel nonlinear joint inversion techniques for Rayleigh and Love waves: Pearson correlation coefficient and thickness mean sharing. The Pearson correlation coefficient approach employs the Pearson correlation coefficient and alternating iterative objective functions to synchronize the shear wave velocity structures derived from Rayleigh and Love waves, thereby enhancing the accuracy of the joint inversion. Conversely, the thickness mean sharing method computes an average of the thickness values obtained in each iteration of the inversion, utilizing the traditional joint inversion objective function. Tests on three distinct stratigraphic structures—characterized by increasing velocity, high‐speed hard interlayers and low‐speed soft interlayers—as well as on measured data, demonstrate that the proposed methods significantly improve the stability and accuracy of nonlinear joint inversion. [ABSTRACT FROM AUTHOR]

Solving mathematical story problems has proven to be a challenge for primary school students with and without developmental disabilities. The present study replicates a behavior analytic study (Neef et al.) by teaching three autistic Chinese students in inclusive education classes to solve addition/subtraction story problems by acquiring an overt precurrent behavior chain. The intervention was effective for all participants by employing a multiple baseline design across behaviors. Additionally, the study extends Neef et al. by conducting maintenance, generalization, and social validity assessments, and expands the teaching format to distance learning (telehealth). The results and limitations are discussed based on Skinner's conceptualization of problem‐solving and its clinical application in teaching complex mathematical skills to students with developmental disabilities. [ABSTRACT FROM AUTHOR]

The purpose of this study was to replicate previous research that examined the effects of tact and listener instruction on the emergence of bidirectional intraverbals, and to extend this research line to include teaching a foreign language to students with autism spectrum disorders (ASD) via telehealth. The study participants were four Chinese native primary school‐aged students. An adaptive alternative treatment design was used to compare the effects of tact and listener instruction on bidirectional intraverbals, and pre‐probe and post‐probe data demonstrated that both forms of instruction led to bidirectional intraverbal relations, with tact instruction being relatively more effective. Maintenance and social validity were assessed for all participants, and booster instructions were provided as needed. The results were discussed in the context of inclusive education and improving foreign language instruction for students with special needs. [ABSTRACT FROM AUTHOR]

Surgical resection of glioblastoma multiforme (GBM) often results in tumor recurrence and mild neurologic deficits. Here, a 3D asynchronous drug delivery system is innovatively developed to address the dual challenges of GBM recurrence and postoperative neurological deficit. Based on transcriptome analysis of tumor cells and tumor microenvironment (TME) cells between primary and recurrent mouse GBM tissues, a novel dual‐targeting approach is developed to combine mTOR pathway inhibition with microglia/macrophage repolarization. Then, in situ injectable methacrylated gelatin (GelMA) is constructed to perfectly fit into the tumor resection cavity and achieve direct delivery of dual‐targeted drugs, exhibiting outstanding postoperative GBM inhibitory effects in vivo. At the same time, neurotrophic factor‐saturated 3D‐printed GelMA patches are used to construct a 3D asynchronous drug delivery system, allowing gradual penetration of the neurotrophic factors into the underlying hydrogel to promote axonal sprouting after GBM suppression. Notably, this 3D asynchronous drug delivery system promotes neurological recovery without weakening the efficacy of inhibiting tumor recurrence. Therefore, this study not only proposes a new dual‐targeted GBM treatment strategy but also pioneers the construction of a 3D asynchronous drug delivery system for the comprehensive treatment of GBM. This study is expected to improve the poor prognosis of patients with GBM. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) ranks among the most prevalent malignancies worldwide, characterized by its complex etiology and slow research progress. Diabetes, as an independent risk factor for CRC, has been widely certified. Consequently, this study centers on elucidating the intricacies of CRC cells initiation and progression within a high‐glucose environment. Methods: A battery of assays was employed to assess the proliferation and metastasis of CRC cells cultured under varying glucose concentrations. Optimal glucose levels conducive to cells' proliferation and migration were identified. Western blot analyses were conducted to evaluate alterations in apoptosis, autophagy, and EMT‐related proteins in CRC cells under high‐glucose conditions. The expression of PI3K/AKT/mTOR pathway‐associated proteins was assessed using western blot. The effect of high glucose on xenograft growth was investigated in vivo by MC38 cells, and changes in inflammatory factors (IL‐4, IL‐13, TNF‐α, IL‐5, and IL‐12) were measured via serum ELISA. Results: Our experiments demonstrated that elevated glucose concentrations promoted both the proliferation and migration of CRC cells; the most favorable glucose dose is 20 mM. Western blot analyses revealed a decrease in apoptotic proteins, such as Bim, Bax, and caspase‐3 with increasing glucose levels. Concurrently, the expression of EMT‐related proteins, including N‐cadherin, vimentin, ZEB1, and MMP9, increased. High‐glucose cultured cells exhibited elevated levels of PI3K/AKT/mTOR pathway proteins. In the xenograft model, tumor cells stimulated by high glucose exhibited accelerated growth, larger tumor volumes, and heightened KI67 expression of immunohistochemistry. ELISA experiments revealed higher expression of IL‐4 and IL‐13 and lower expression of TNF‐α and IL‐5 in the serum of high‐glucose‐stimulated mice. Conclusion: The most favorable dose and time for tumor cells proliferation and migration is 20 mM, 48 h. High glucose fosters CRC cell proliferation and migration while suppressing autophagy through the activation of the PI3K/AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI), recognized as the world's most serious public health problem, currently lacks effective treatment options. The development of the patch has great clinical significance whether it is used as a skull implant material or TBI repair. In response to this critical health challenge, a novel 3D‐printed bi‐layer cranial‐brain patch (SMB6) with dual functionality, addressing both TBI repair and skull regeneration, is developed. In the first layer, the incorporation of high concentrations of mesoporous bioactive glass nanoparticles establishes a microenvironment for bone regeneration. Meanwhile, the second layer, comprised of methacrylated silk fibroin hydrogel, provides essential mechanical support for nanocell membrane vesicles loaded with macrophage colony‐stimulating factor and interleukin‐6. This innovative design aims to interrupt the cascade of secondary brain injury. In experimental models of TBI, SMB6 demonstrates remarkable efficacy in inhibiting brain edema, exerting therapeutic effects on blood vessels, nerves, and inflammation. Additionally, promising outcomes are observed in promoting bone regeneration in skull defect models. This work not only introduces a potential therapeutic patch for TBI‐related diseases but also provides novel insights for the clinical translation of cranial patches. [ABSTRACT FROM AUTHOR]

The Rh(III)‐catalyzed ortho alkylation of N‐pyridylcarbazoles with nitroalkenes has been developed, furnishing a wide range of 2‐(2‐nitroalkyl)carbazoles. Both aromatic and aliphatic nitroalkenes participated in this alkylation reaction successfully. This protocol also proceeded well with an indoline based substrate. Derivatization of the representative nitroalkane product was described. [ABSTRACT FROM AUTHOR]

Food stealing is often a serious behavioral problem among children with diagnoses of autism and other developmental disorders. Very few empirical studies concerning this behavioral challenge have been reported. We applied a correspondence training procedure to teach self‐control as replacement behavior to four children with autism and developmental disorders who displayed food stealing in the community. A changing criterion design embedded within a nonconcurrent multiple‐probe across participants design was used. The treatment succeeded for all four participants by increasing latency to eating highly preferred food to a predetermined criterion and reducing occurrences of food stealing to zero. Three participants generalized the replacement behavior to natural settings and maintained the behavior for 2 weeks, 1 month, 2 months, 3 months, and 4 months. One participant without expressive language was taught successfully during treatment trials but failed to maintain and generalize the behavior. A functional relation between delaying food eating and Say‐Do correspondence training was demonstrated. [ABSTRACT FROM AUTHOR]

Biophysical effects of forest cover changes are often neglected by climate policies and recent state‐of‐the‐art climate models exhibit wide spreads in simulating the biophysical impacts of deforestation. By using the CMIP6‐LUMIP simulations, here we examined the biophysical impacts of deforestation on global temperature and attributed deforestation‐induced surface temperature change to different biophysical effects (i.e., radiative forcing, aerodynamic resistance, Bowen ratio and atmospheric feedbacks) at regional scales. Results show that models agree on the sign of temperature responses to different biophysical factors in the tropics, but exhibit wide divergence in the extratropical regions. Among the three local biophysical factors (i.e., radiative forcing, aerodynamic resistance, and Bowen ratio), aerodynamic resistance contributes largely to local surface warming in models. As the local effects rarely affect the areas away from the deforested regions, much of the modeled discrepancies result from non‐local atmospheric feedbacks in the middle and high latitudes. Our results suggest that climate responses to deforestation have a large spread in current models and highlight the need to improve our understanding and modeling of non‐local effects in the biophysical impacts of deforestation. Plain Language Summary: The Land Use Model Intercomparison Project (LUMIP) multimodel simulations with a common experimental protocol provide a great opportunity to explore the biophysical effects of land use and land cover change and allow a direct comparison of model responses to deforestation. By analyzing the CMIP6‐LUMIP multimodel simulations, we show that deforestation causes widespread summer warming in the tropics, but the simulated temperature changes in response to deforestation diverge in the middle and high latitudes. We further attributed deforestation‐induced surface temperature change to different biophysical effects (radiative forcing, aerodynamic resistance, Bowen ratio and atmospheric feedbacks). Our results indicate that atmospheric feedbacks play the dominant role in determining the temperature responses, and aerodynamic resistance also matters. The atmospheric feedbacks in the temperate and boreal regions are highly model‐dependent. Further efforts to explore the non‐local influence of temperate deforestation using state‐of‐the‐art climate models are needed. Key Points: Our study assesses different biophysical impacts of deforestation on surface temperature in CMIP6 modelsCMIP6 models show wide divergence on the surface temperature changes in the extratropical regions due to non‐local atmospheric feedbacksChanges in the aerodynamic resistance dominate the surface temperature response to local biophysical effects of deforestation [ABSTRACT FROM AUTHOR]

We aim to investigate the roles and mechanisms of NR3C2 in colorectal cancer (CRC). The expression of NR3C2 in CRC tumours and paired paracancerous tissues of 71 CRC patients and five CRC cell lines was detected by western blotting, immunohistochemistry and real‐time reverse‐transcription PCR. Moreover, NR3C2 was overexpressed or knocked down in CRC cells by lentiviral vector transfection. The proliferation of cells was measured by MTT, colony formation assay and flow cytometry. Glucose metabolism was assessed by detecting lactate production, glucose consumption and ATP production. Western blotting and real‐time reverse‐transcription PCR were used to detect the expression of AMPK, LDHA and HK2. The expression of NR3C2 was significantly decreased in CRC tumours compared to paracancerous tissues, which was correlated with distant metastasis, poor prognosis and advanced stages of CRC patients. Overexpressing NR3C2 suppressed the proliferation and promoted the G2/M cell cycle arrest of CRC cells. Furthermore, NR3C2 inhibited glucose metabolism by decreasing the expression of HK2 and LDHA. The phosphorylation of AMPK was also downregulated in CRC cells overexpressing NR3C2. This study demonstrated that NR3C2 inhibited the proliferation of CRC by inhibiting glucose metabolism and phosphorylation of AMPK which may serve as a therapeutic target for CRC. [ABSTRACT FROM AUTHOR]

Previous studies documented that near‐surface temperatures over the Sahara and Arabian deserts have been amplified in a warming climate, which is termed desert amplification (DA). DA has been linked possibly to the large‐scale greenhouse effects associated with increasing water vapour. With very limited moisture availability over the driest desert, two key questions unanswered are the desert moisture sources and the relative contributions of thermodynamic and dynamic processes to the changes in moisture transport. In this study, the atmospheric water vapour budget over the Sahara Desert from 1981–2020 is analysed to address these two questions. Results indicate that the water vapour content over the Sahara Desert has increased significantly since 1981, primarily during the boreal summer and in the lower to middle troposphere. The water vapour budget analysis indicates that in the boreal summer, most of the added moisture is transported into the Sahara Desert through the intensifying northerly inflow across the northern boundary of the desert, while the other boundaries are all export channels. The northerly inward moisture transport is associated with the ridge in the lower troposphere and the Saharan high above the lower troposphere. Further analysis indicates that both dynamic and thermodynamic factors contribute to the increase of the inward moisture flux at the northern boundary, while the associated interannual variability is dominated by the dynamic component related to the circulation pattern changes. The changes of the circulation pattern in the lower troposphere are manifested as the westward extension of the low over the Arabian Peninsula and as the strengthening of the Saharan high above the lower troposphere, both contributing to the increase of the northerly inward moisture transport. [ABSTRACT FROM AUTHOR]

Long‐span bridges are susceptible to vortex‐induced vibration (VIV), which affects the serviceability and safety of bridges when the vibration amplitude is too large and lasts for a long time. Traditional contact‐type sensing technologies (i.e., accelerometers and linear variable differential transformer) are inconvenient and dangerous to be installed on long‐span bridges for monitoring VIV events. To address this limitation, this article focuses on the VIV measurement of a long‐span suspension bridge through noncontact sensing strategies. The contribution of this article lies in (1) noncontact sensing technologies including microwave radar, optical camera and video equipment were employed to measure multiple‐point displacements of the studied bridge under VIV events; (2) dynamic properties of the bridge (i.e., natural frequency, damping ratio, mode shapes) and characteristics of the VIV event (i.e., single‐mode vibration and dominant vibration mode switch) were identified by analyzing monitoring data; (3) an early warning framework for VIV event of long‐span suspension bridges was proposed based on monitored dynamic responses and wind fields; specifically, two indicators, the dominant vibration frequency and the similarity between bridge shape and vibration mode shape, were proposed to identify the VIV event, and then the root mean square (RMS) of measured response was further calculated to determine whether there is a need to trigger the warning system or not. The proposed noncontact VIV measurement strategy has the advantage of rapid measurement of vibration magnitude, rapid identification of dynamic properties of the studied bridge and characteristics of the VIV event, which are helpful for the government and bridge owners to make decisions on vibration mitigation measures and to avoid safety issues. [ABSTRACT FROM AUTHOR]

Bacterial infection is one of the most frequent complications in the burn and chronic wounds. Inspired by natural existing superhydrophobic surface structures, a novel asymmetric wettable membrane was prepared using the electrospinning technique for facilitating the bacteria‐infected wound healing. Herein, the prepared membrane consists of two layers: The hydrophobic outer layer was composed of poly (lactic‐co‐glycolic) acid (PLGA) and black phosphorus‐grafted chitosan (HACC‐BP), while the hydrophilic inner layer was composed by using a mixture of gelatin (Gel) with ginsenoside Rg1 (Rg1). Biological studies in vitro showed BP@PLGA/Gel (BP@BM) membrane with excellent antibacterial activity could significantly inhibit the adhesion of bacteria, and Rg1 could facilitate the migration and tube formation of human umbilical vein endothelial cells (HUVECs). Compared to Aquacel Ag dressing, the result in vivo revealed that the Rg1/BP@BM could facilitate better wound healing by triggering phosphoinositide 3‐kinase (P‐PI3K/PI3K) and phosphorylation of protein kinase B (P‐AKT/AKT) signaling pathways, upregulating Ki67, CD31, α‐SMA, and TGF‐β1, and downregulating TNF‐α, IL‐1β, and IL‐6, promoting M2 polarization (IL‐10, CD206, and Arg‐1) of macrophages, inhibiting M1 polarization (iNOS) of macrophages. These findings suggested that the asymmetric wettable membrane have the huge potential for wound healing. [ABSTRACT FROM AUTHOR]

The Congo rainforest located in central equatorial Africa is an important, yet understudied part of the globe surrounded by complex orographic features. A primitive understanding of precipitation processes such as mesoscale convective dynamics magnifies uncertainties in the future climate projections of the hydrological cycle over the Congo. Furthermore, the effects of orography, which is an important forcing for convection and precipitation, are poorly resolved by climate models, and ill‐conceptualized over the Congo. To address this knowledge gap, perturbed orographic forcing experiments are conducted using the Weather Research and Forecasting (WRF) mesoscale numerical model in a high‐resolution convection‐permitting model setup. The model simulated selected dates in November 2014. The thunderstorms and rainfall simulated in the control run for the case study analyzed in this article compared reasonably well to satellite‐derived brightness temperature and rainfall data. The results from this case study show that the dynamical impact of increasing the height of the East African Highlands is the blocking of the lower‐tropospheric tropical easterlies. This weakening of the lower‐tropospheric zonal winds increases the windshear over the Congo Basin resulting in slower propagating, more intense mesoscale convective systems with enhanced rainfall. [ABSTRACT FROM AUTHOR]

Maleimides and succinimides are all vital scaffolds in biological fields and various natural products. Maleimide derivatives have been extensively used as coupling partners for various organic transformations, affording a broad array of important molecular architectures including succinimides. In the past decade, a variety of efficient chelation‐assisted strategies have been employed for the selective addition of C−H bonds to maleimides giving succinimides, which are also highly important building blocks in organic synthesis. This Review provides an overview of research progress relating to maleimides participated transition‐metal‐catalyzed group‐directed C−H alkylation from 2012 to 2021. Significant advances in this field were highlighted, diverse transition metal catalysts, organic substrates contained different directing groups, reaction mechanisms as well as synthetic applications are systematically discussed. In addition, the limitations and intractable issues need to be solved in the future are also pointed out. [ABSTRACT FROM AUTHOR]

Previous studies show that the environment in the Guangdong, Hong Kong, and Macao region is under the double stress of global warming and urbanization. Here, we show that due to the increase of regional greenness, the effect of urbanization warming on surface air temperature (SAT) decreased with time and became statistically insignificant from 2004 to 2018, compared to 1979 onward; while the urbanization itself has significantly warmed land surface temperature (LST), with a warming rate of 0.14°C ± 0.04°C/10a at daytime and 0.02°C ± 0.02°C/10a at nighttime during 2004–2018, respectively. The anthropogenic heat was found to have a limited influence on SAT, but more significant and tangible effects on LST. It is essential to improve the control of additional warming effects caused by urbanization. Plain Language Summary: The Guangdong, Hong Kong, and Macao region is the most economically developed region in China, and the urbanization impact on the regional warming is frequently discussed during recent decades. We found that the urbanization warming on surface air temperature (SAT) has decreased to insignificant during the recent decade due to regional greening, while the warming of land surface temperature (LST) remains tangible. This result is related to the different effects of two moderating drivers (anthropogenic heat and vegetation index) on both SAT and LST. Thus, it is essential to increase urban greenness and reduce anthropogenic heat fluxes in parallel. Key Points: The effect of urbanization on the surface air temperature (SAT) decreases over time as regional vegetation greening increasesThe urbanization effect on the land surface temperatures (LSTs) from the long time series of satellite retrievals remains significantThe anthropogenic heat was found to have a limited influence on SAT, but more significant and tangible effects on LST [ABSTRACT FROM AUTHOR]

The recent summer surface air temperature (SAT) changes over densely populated Eurasia exhibit a non‐uniform pattern with amplified warming over Europe and East Asia (EA) but weak warming over Central Asia (CA), forming a wave train‐like structure. However, the key factors that determine this non‐uniform warming pattern remain unclear. By analyzing observations and model simulations, here, we show that more than half of the SAT multidecadal variations from 1950 to 2014 over Europe‐west Asia and EA may have resulted from external forcing, rather than from internal variability in the Atlantic as previously thought. In contrast, the recent SAT over CA is influenced mainly by internal variations in the Atlantic and Pacific oceans. Large ensemble model simulations suggest that the forced SAT multidecadal variations over Eurasia are mainly caused by changes in greenhouse gases and aerosols. Our findings provide strong evidence for major impacts of external forcing on multidecadal climate variations over Eurasia. Plain Language Summary: Previous studies have documented non‐uniform decadal warming rates in summer since the mid‐1990s over densely populated Eurasia, with amplified warming over Europe and East Asia (EA) but weak warming over Central Asia. This unique tripole warming pattern and its cause have attracted considerable attention. It may arise from internal variability (IV; e.g., Atlantic Multidecadal Oscillation [AMO]) and/or external forcing. Furthermore, it was found that the recent AMO resulted from both IV and decadal changes in aerosols. Thus, the relative contributions of IV and external forcing to the recent Eurasian warming pattern remain unclear. Here we show that the surface air temperature multidecadal variations since 1950 over Eurasia are caused by both IV and external forcing, with more than half of the variations over Europe‐west Asia and EA resulted from external forcing (i.e., greenhouse gases [GHGs] and aerosols), in contrast to the previous notion that the non‐uniform warming is mainly originated from the Atlantic Ocean. Looking ahead into the upcoming decades, aerosols will continue to decrease, whereas the AMO will likely be in its positive phase. These changes, together with continued increases in GHGs, will accelerate warming trends over Eurasia and further exacerbate summer heat waves. Key Points: More than half of the multidecadal surface air temperature (SAT) variations from 1950 to 2014 over Europe‐west Asia and East Asia resulted from external forcingThe forced SAT multidecadal variations over Eurasia are mainly caused by changes in greenhouse gases and aerosolsOur study helps reconcile human and natural drivers of the tripole pattern of multidecadal summer temperature variations over Eurasia [ABSTRACT FROM AUTHOR]

Molybdenum sulfide has great potential for the electrocatalytic hydrogen evolution, but its structural instability in acidic media and high barriers in alkaline/neutral media limits its practical applications. Herein, the design of monodispersed sandwich‐structured MoO2/MoS2/C hollow nanoreactors is reported with a triple layer "conductor/catalyst/protector" configuration for efficient electrochemical hydrogen evolution over all pH values. Metallic MoO2 substrates with ultrahigh pristine electroconductivity can promote the charge transfer while sulfur vacancies are introduced to activate the highly exposed (002) facets of MoS2. The optimized MoO2/MoS2/C nanoreactor exhibits overpotentials of 77, 91, and 97 mV (10 mA cm−2) and Tafel slopes of 41, 49, and 53 mV dec−1 in acidic, alkaline, and neutral media, respectively, which are much better than most of the MoS2‐based electrocatalysts. Moreover, defective carbon shells are in situ generated, preventing the electrocatalysts from corrosion in acidic and alkaline media; the structural stability is verified via in situ Raman and XRD characterizations. Based on the density functional theory calculations, vacancy engineering can regulate the band structures, electron density differences, total density of states, and the H* and H2O adsorption‐dissociation ability over the entire pH range. The findings may shed light on the rational development of practical pH‐universal electrocatalysts for durable hydrogen evolution. [ABSTRACT FROM AUTHOR]

Using observational rainfall datasets, we identify a positive correlation between precipitation over Central Equatorial Africa (CEA) and the Indian Ocean Dipole (IOD) during September‐December (SOND) for the period 1981–2019. Rainfall amount significantly increases during positive IOD events. The enhancement in precipitation is primarily attributed to increased rainfall frequency and reaches the maximum in October. IOD impacts rainfall via modifying the Walker circulation over the tropical Indian Ocean and moisture in the middle troposphere over CEA. The Madden‐Julian Oscillation (MJO) activity covaries with IOD to modulate the African Easterly Jet, which is critical to convection development over CEA. SOND rainfall has increased for the last two decades, which is concurrent with increases in both the IOD index and the correlation between IOD and rainfall. The IOD‐congruent rainfall changes potentially account for much of rainfall trends in southern and eastern CEA. Plain Language Summary: Tropical Africa is one of the convective hotspots. Understanding causes of rainfall variations is crucial for both local ecosystem and rainfall‐fed agriculture and society. Here we show that there is a significant positive correlation between CEA rainfall and Indian Ocean Dipole (IOD) during SOND. During positive IOD events, the warmer western Indian Ocean favoring stronger convection and wetter atmosphere to increase rainfall amount and frequency. An increase in rainfall has been observed since the 1990s and is concurrent with the increasing correlation between IOD and rainfall. The increasing IOD index might contribute to much of the rainfall trends over the western, southern, and eastern basin. Thus, IOD variability would provide indications for improving seasonal weather predictions under the changing climate and agricultural developments in CEA. Key Points: There exists a positive correlation between rainfall over Central Equatorial Africa (CEA) and Indian Ocean Dipole (IOD) during September‐DecemberPositive IOD events increase rainfall amount and frequency by modifying the Walker circulation, moisture, and the Madden‐Julian OscillationIncreasing CEA rainfall during the last two decades is potentially attributed to increasing influence of IOD [ABSTRACT FROM AUTHOR]

Background: It has been reported that the polyadenylate‐binding protein‐interacting protein 1 (PAIP1) pathway is closely connected with the progression of some malignant tumors. Here we examined the potential functional mechanism of PAIP1 in tongue squamous cell carcinoma (TSCC). Methods: PAIP1 was knocked down in TSCC cell lines and proliferation and apoptosis in vitro analyzed. The molecular features of TSCC were determined using quantitative proteome and succinylome analyses. The results were confirmed in the mouse model. Results: PAIP1 promoted cell proliferation and inhibited apoptosis. Its knockdown decreased Ki67 and Pcna expressions and increased Bax/Bcl2 index and Caspase‐3 expression. Bioinformatics analysis for proteomics revealed that PAIP1 knockdown correlated with the changes in differential protein expression. Conclusions: Upregulation of PAIP1 induces cell proliferation and inhibits apoptosis in TSCC; PAIP1 might be a diagnostic biomarker and a significant drug target. [ABSTRACT FROM AUTHOR]

The Rh(III)‐catalyzed C2‐alkylation of indoles with maleimides is disclosed under additive‐free conditions by employing pyridine as a removable directing group. This protocol features low catalyst loadings, simple reaction conditions and good functional group tolerance. In addition to various indoles and maleimides, arenes, pyrroles, maleates as well as ethyl acrylates are applicable substrates. [ABSTRACT FROM AUTHOR]

Intercalation chemistry/engineering has been widely investigated in the development of electrochemical energy storage. Graphite, as an old intercalation host, is receiving vigorous attention again via a new halogen intercalation. Whereas, exploiting new intercalation hosts and optimizing the intercalation effect still remains a great challenge. This study fabricates a Cu2Se intercalation compound showing expanded interlayer space and nanosheet array features by using a green growth approach, in which cetyltrimethyl ammonium bromide (CTAB) is inserted into Cu2Se at an ambient temperature. When acting as an electrode material for sodium‐ion batteries, the Cu2Se–CTAB nanosheet arrays exhibit excellent discharge capacity and rate capability (426.0 mAh g−1 at 0.1 A g−1 and 238.1 mAh g−1 at 30 A g−1), as well as high capacity retention of ≈90% at 20 A g−1 after 6500 cycles. Benefiting from the porous array architecture, the transport of electrolytes is facilitated on the surface of Cu2Se nanosheets. In particular, the CTAB intercalated in the interlayer space of Cu2Se can increase its buffer space, stabilize the polyselenide shuttle, and prevent the fast growth of Cu nanoparticles during its electrochemical process. [ABSTRACT FROM AUTHOR]

In the present work, a novel database of drug compounds and a rapid screening method based on ultra‐high performance liquid chromatography coupled to high resolution orbitrap mass spectrometry were developed and applied in the screening and identification of targeted and nontargeted antihypertensive adulterants in dietary supplements and herbal medicines. The established screening database includes retention time, exact mass, fragments, isotopic pattern, and MS2 spectra library of the target compounds and thus provides automated search and identification of the targets with a single injection. The nontargeted compounds in the samples are identified through the full MS scan and MS2 data by using the Chemspider database and the data analysis in XCalibur, MassFrontier and TraceFinder software. In addition, this method possesses excellent quantitative capacity. The novel approach was applied to 65 batches of samples that are claimed as "all‐natural" products having the antihypertensive function, among which nine batches were found to be positive. Multiple targeted and nontargeted antihypertensive adulterants were detected at levels ranging from 2.8 to 27.9 mg/g. The novel database and screening method demonstrated herein will be promising and powerful tools for rapid screening of antihypertensive adulterants in dietary supplements and herbal medicines. [ABSTRACT FROM AUTHOR]

Determination of the absolute configuration (AC) of chiral molecules is a key issue in many fields related to chirality such as drug development, the asymmetric reaction screening, and the structure determination of natural compounds. Although various methods, such as X‐ray crystallography and NMR spectroscopy, are used to determine the AC, a simple and cheap alternative method is always anticipated. So far, electronic circular dichroism (ECD) spectroscopy has been widely used to ascertain the AC and enantiomeric excess (ee) values by applying appropriate organic probes. Here, circularly polarized luminescence (CPL) spectroscopy was applied to determine the AC and ee values of a series of amino acid and amino alcohol. The measurements were conducted by mixing the amino acids or amino alcohols with an achiral 1‐hydroxy‐2‐naphthaldehyde. Upon in situ formation of the Schiff base complexes, the system showed emission enhancement and CPL in the presence of Al3+, whose intensity and sign can be used to assign the chiral sense of the amino acids and amino alcohols. The authenticity of the method was further compared with the established CD spectroscopy, revealing that CPL spectra of formed Al3+ complex were effective to determine the AC of chiral species. [ABSTRACT FROM AUTHOR]

This article was designed by using a network pharmacological approach to reveal the therapeutic targets and molecular mechanisms of oxyresveratrol (Oxyres) treating colorectal cancer (CRC). Furthermore, several bioinformatic findings would be validated. Pathogenetic targets of CRC and pharmacological targets of Oxyres were identified by web‐available databases. All identifiable biotargets were collected for functional enrichment analyses to reveal the biological processes and signaling pathways of Oxyres treating CRC. In addition, human CRC, non‐CRC samples, and cell line study were used to validate the predictive biotargets of Oxyres treating CRC. In network pharmacological analyses, top therapeutic targets of mitogen‐activated protein kinase 1 (MAPK1), insulin growth factor 1 (IGF1), hematopoietic prostaglandin D synthase (HPGDS), GTPase HRas (HRAS), and cytochrome P450 2C9 (CYP2C9) in Oxyres treating CRC were identified, respectively. As shown in functional analysis, biological processes of Oxyres treating CRC were mainly involved in modulating cell communication, signal transduction, apoptosis, cell motility, cell proliferation, and lipid metabolism. Furthermore, top 10 signaling pathways of Oxyres treating CRC were identified, respectively. In human study, CRC samples resulted in increased neoplastic expressions of Ki‐67, MAPK1, IGF1, characterized with clinical imaging inspection, pathological diagnosis, and altered blood lipids in these CRC cases. In cell culture study, Oxyres‐dosed CRC cells exhibited reduced cell proliferation, promoted cellular apoptosis. Furthermore, significantly decreased proteins of intracellular Ki‐67, MAPK1, and IGF1 were observed in Oxyres‐dosed cells when compared to those in controls. Collectively, anti‐CRC pharmacological activity of Oxyres may be mainly associated with induction of apoptosis and suppression of cell proliferation as revealed in bioinformatic findings. In addition, all core biotargets and molecular mechanisms of Oxyres treating CRC are unveiled respectively. Interestingly, the identifiable MAPK1, IGF1 biotargets may be potential molecules for treating and screening CRC. [ABSTRACT FROM AUTHOR]

Spatiotemporal information of the vehicles on a bridge is important evidence for reflecting the stress state and traffic density of the bridge. A methodology for obtaining the information is proposed based on computer vision technology, which contains the detection by Faster region‐based convolutional neural network (Faster R‐CNN), multiple object tracking, and image calibration. For minimizing the detection time, the ZF (Zeiler & Fergus) model with five convolutional layers is selected as the shared part between Region Proposal Network and Fast R‐CNN in Faster R‐CNN. An image data set including 1,694 images is established about eight types of vehicles for training Faster R‐CNN. Combined with the detection of each frame of the video, the methods of multiple object tracking and image calibration are developed for acquiring the vehicle parameters, including the length, number of axles, speed, and the lane that the vehicle is in. The method of tracking is mainly based on the judgment of the distances between the vehicle bounding boxes in virtual detection region. As for image calibration, it is based on the moving standard vehicles whose lengths are known, which can be regarded as the 3D template to calculate the vehicle parameters. After acquiring the vehicles' parameters, the spatiotemporal information of the vehicles can be obtained. The proposed system has a frame rate of 16 fps and only needs two cameras as the input device. The system is successfully applied on a double tower cable‐stayed bridge, and the identification accuracies of the types and number of axles are about 90 and 73% in the virtual detection region, and the speed errors of most vehicles are less than 6%. [ABSTRACT FROM AUTHOR]

By analyzing observations and model simulations, here we show that there exists a significant anticorrelation on interannual to multidecadal time scales between the Sahel and southeast Amazon rainfall during July‐August‐September. This rainfall seesaw, which is strongest on decadal to multidecadal scales, is due to an anomalous meridional gradient of sea surface temperatures across the tropical Atlantic that pushes the Intertropical Convergence Zone and its associated rain belt toward the anomalously warm hemisphere. Large ensemble model simulations suggest that the seesaw pattern is likely caused by decadal changes in anthropogenic and volcanic aerosols, rather than internal climate variability. Our results suggest that the recent decadal to multidecadal climate variations in and around the North Atlantic basin are largely externally forced and that projected large North Atlantic warming could lead to a wetter Sahel but drier Amazon in the future. Plain Language Summary: Both the semiarid Sahel and Amazon rain forest are known hot spot regions of climate change. However, the causes of Sahelian and Amazonian rainfall variations are still debated and the scientific community has often examined these two regions separately rather than collectively. Here we show that there exists a significant decadal rainfall seesaw pattern between the Sahel and southeast Amazon during July‐August‐September in observations and coupled model simulations. This seesaw pattern is likely caused externally by decadal changes in anthropogenic and volcanic aerosols, rather than internal climate variability. Our findings not only detect and attribute the seesaw pattern over the Sahel and Amazon Basin but also provide further evidence for major impacts of external forcing on recent decadal climate variations in and around the North Atlantic Ocean. Key Points: There exists a significant anti‐correlation on decadal time scales between the Sahel and southeast Amazon rainfall during July‐SeptemberLarge ensemble model simulations suggest that the seesaw pattern is likely caused by decadal changes in anthropogenic and volcanic aerosolsRecent decadal to multidecadal climate variations in and around the Atlantic basin are largely externally forced [ABSTRACT FROM AUTHOR]

Abstract: Layered transition metal sulfides (LTMSs) have tremendous commercial potential in anode materials for sodium‐ion batteries (SIBs) in large‐scale energy storage application. However, it is a great challenge for most LTMS electrodes to have long cycling life and high‐rate capability due to their larger volume expansion and the formation of soluble polysulfide intermediates caused by the conversion reaction. Herein, layered CuS microspheres with tunable interlayer space and pore volumes are reported through a cost‐effective interaction method using a cationic surfactant of cetyltrimethyl ammonium bromide (CTAB). The CuS–CTAB microsphere as an anode for SIBs reveals a high reversible capacity of 684.6 mAh g−1 at 0.1 A g−1, and 312.5 mAh g−1 at 10 A g−1 after 1000 cycles with high capacity retention of 90.6%. The excellent electrochemical performance is attributed to the unique structure of this material, and a high pseudocapacitive contribution ensures its high‐rate performance. Moreover, in situ X‐ray diffraction is applied to investigate their sodium storage mechanism. It is found that the long chain CTAB in the CuS provides buffer space, traps polysulfides, and restrains the further growth of Cu particles during the conversion reaction process that ensure the long cycling stability and high reversibility of the electrode material. [ABSTRACT FROM AUTHOR]

Abstract: Microphase‐separated structures of block copolymers (BCs) with a size of sub‐10 nm are usually obtained by hydrogen‐bond‐induced self‐assembly of BCs through doping with small molecules as functional additives. Here, fabrication of hierarchically self‐assembled sub‐10 nm structures upon microphase separation of amphiphilic liquid‐crystalline BCs (LCBCs) at the existence of hydrogen bonds but without any dopants is reported. The newly introduced urethane groups in the side chain of the hydrophobic block of LCBCs interact with the ether groups of the hydrophilic poly(ethylene oxide) (PEO) block, leading to imperfect crystallization of the PEO blocks. Both crystalline and amorphous domains coexist in the separated PEO phase, enabling a lamellar structure to appear inside the PEO nanocylinders. This provides an elegant method to fabricate controllable sub‐10 nm microstructures in well‐defined polymer systems without the introduction of any dopants. [ABSTRACT FROM AUTHOR]

Asymptotic homogenization method, magneto-electro-elastic, microscopic multi-physics coupling, stabilized node-based smoothed radial point interpolation method Errata: "Stabilized node-based smoothed radial point interpolation method for micromechanical analysis of the magneto-electro-elastic structures in thermal environment". [Extracted from the article]

Shale oil exploration of the Permian Lucaogou Formation (P2l) has greatly advanced in the Jimusar Sag in the Junggar Basin. However, despite the strong exploration prospects of shale oil resources, the potential of shale oil resources in the Junggar Basin has been insufficiently assessed. This study performs systematical evaluation of P2l source rocks in the Jimusar Sag and proposes an improved hydrocarbon generation potential method to assess the hydrocarbon generation and expulsion characteristics and evaluates the shale oil resource potential of the P2l source rocks in the Jimusar Sag. The results show that the P2l source rocks are thick (up to 200 m) and are distributed over a wide area (up to 1200 km2) in the study region. It contains high TOC (2%-5%), characterized by dominantly type I and type II kerogen. The source rocks are in the low mature-mature stage, and possess good conditions for generation of hydrocarbons. The P2l source rocks reached the hydrocarbon expulsion threshold at a thermal maturity of 0.8% vitrinite reflectance. The efficiency of hydrocarbon expulsion of the source rock is 34%. The amounts of hydrocarbons generated and expelled were 65 × 108 t. Based on the above information, the shale oil resources potential is calculated to be 43 × 108 t, indicating very good shale oil resource prospect in the P2l source rocks of the Jimusar Sag. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT North China is one of the most densely populated regions in the world. To its west, north, and northwest, the world's largest afforestation project has been going on for decades. At the same time, North China has been suffering from air pollution because of its large fossil fuel consumption. Here we show that the changes in land cover and aerosol concentration are coupled with the variations of land surface temperature, cloud cover, and surface solar radiation during the summer 2000-2013. Model experiments show that the interannual variation of aerosol concentration in North China is mainly a result of the varying atmospheric circulation. The increasing vegetation cover due to afforestation has enhanced surface evapotranspiration ( ET) and cooled the local surface, and precipitation is observed to be increasing with ET. The model with prescribed increasing vegetation cover can simulate the increasing ET but cannot reproduce the increasing precipitation. Although this may be caused by model biases, the lack of aerosol processes in the model could also be a potential cause. [ABSTRACT FROM AUTHOR]

A miniaturised low‐profile frequency selective surface structure (FSSs) with highly angular stability is proposed in this Letter. Due to the strong coupling introduced by the thin dielectric, the designed FSS has a miniaturised unit size of 0.28λ, which can be applied to millimetre‐wave communication. To better analyse the structure performance, the equivalent circuit model (ECM) is proposed. Moreover, the prototype with the centre working frequency of 30 GHz is fabricated and measured to verify the design. The insertion loss is demonstrated <0.12 dB with a bandwidth of 2.5 GHz under the normal incident wave. While the incident angle changes to 60°, it is <1.96 dB. In addition, the transmission zeroes remain at 36.4 GHz, when the incident angle varies from 0° to 60°, which result in a stable stopband following the passband. Particularly, the passband and stopband are controlled by two coupling capacitors, so the passband and stopband can be adjusted independently by changing the different parts of the structure. Finally, the results obtained by the ECM, simulation, and measurement have a good agreement, which demonstrates that the proposed FSS design is a good candidate for millimetre‐wave communication. [ABSTRACT FROM AUTHOR]

ABSTRACT To demonstrate the importance of land use and land cover change ( LUCC) on future climate projections, the CanESM2 model experiments recommended by the LUCID project were used. Four fully coupled simulations were performed: with and without LUCC for two scenarios ( RCP2.6 and RCP8.5). Model results show that the global LUCC effects are very small because of offsetting regional signals. Future global land-use emissions due to LUCC in the two scenarios are estimated to be 35.7 and 32.1 Pg C, respectively. The largest regional responses are directly associated with the land cover conversion in the tropics and subtropics. As the albedo effect dominates in mid- and high-latitudes, LUCC produces a small cooling or little effect in the western United States and Eurasia as a result of the reduction in needleleaf evergreen trees. LUCC increases temperature by 0.05-0.1 °C in the tropics due to the reduction in evapotranspiration because of the conversion from rainforests to croplands. When compared with greenhouse gases ( GHGs) and aerosol influences, LUCC has a second-order effect on the temperature change at the global scale. However, for the CO2 fluxes, the LUCC and GHG/aerosol effects are equally important and the former is much stronger than the latter over some regions such as Africa and South and North America. The land-atmosphere CO2 flux can be regionally modulated by LUCC when compared with the effects of GHG/aerosol forcings. Although there is no significant land cover change in higher latitudes, climate responses to LUCC occur over boreal and arctic regions, indicating that atmospheric teleconnection can modify regional climate far away from the areas with LUCC. These results highlight the need to understand the responses of carbon cycle and remote climate to LUCC over longer time scales. [ABSTRACT FROM AUTHOR]

The article discusses a study concerning the hydrocarbon generation and expulsion characteristics of Permian Lucaogou Formation source rocks in Jimusar Sag, Junggar Basin in China. Topics include the exploration practice in the basin, the organic matter abundance of the formation, and the maturity and characteristics of hydrocarbon generation and expulsion. Methods used in the study include well logging, core logging, and rock-evaluation.

Precipitation-induced sensible heat (HPR) which is transferred between the land surface and rainwater can be extremely large during a heavy precipitation event. Thus, the local surface temperature can be sharply altered on an hourly to daily timescale. However, HPR is commonly neglected in current land surface models because of its small magnitude on long timescales. As a consequence, the simulated land-surface air temperature (TLSA) may be biased. In this study, we use satellite and reanalysis data sets to estimate HPR on the global scale, and we use CESM1 (with CAM4 physics and the prescribed sea surface temperature) to investigate the effect of HPR on TLSA simulations over the second half of the 20th century. Our results show that the reanalysis-estimated HPR is largest over Intertropical Convergence Zone (ITCZ) regions, with seasonal mean values of −0.22 W m−2 (−2.31 to 0.29 W m−2) in DJF and −0.28 W m−2 (−2.89 to 0.24 W m−2) in JJA. These values are consistent with the model-simulated HPR patterns. In DJF, the HPR leads to a weaker equator-pole surface heating difference and therefore, weakens northern stationary waves. The consequent changes of the heat and moisture advection result in noticeable TLSA warming effects (for example, +0.53 K over northern Eurasia and +0.46 K over central North America) and cooling effects (for example, −0.62 K over Alaska and −0.42 K over central Asia) at regional scales. These temperature changes help to reduce the TLSA biases in the model. In JJA, the TLSA changes slightly because of the weak stationary wave responses during the northern summer. [ABSTRACT FROM AUTHOR]

Nobiletin (5, 6, 7, 8, 3′ 4′-hexamethoxyflavone) is a major anticancer component in juice from zhishi (Rutaceae). This study aimed to investigate the inhibitory effect of Nobiletin on hepatic cancer cells both in vitro and in vivo. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), growth curve, and clonogenic assay showed that nobiletin inhibited the proliferation of SMMC-7721 cells in vitro. Hoechst staining observed the characteristics of cell apoptosis in nobiletin-treated cells, and the apoptotic rates of treated groups were increased in a dose-dependent manner. Flow cytometric analysis demonstrated that nobiletin could block the cell cycle arrested at G2 phase. Cell cycle analysis was performed using flow cytometry. Results showed that cell cycle phase distribution analysis showed G2 arrest. It was found that nobiletin downregulated the expressions of Bcl-2 and COX-2 and up-regulated the expressions of Bax and caspase-3 in SMMC-7721 cells by western blotting. The experiment in vivo demonstrated that nobiletin significantly inhibited the growth of H22 transplantable tumor, downregulated the expressions of COX-2, up-regulated the expressions of Bax and caspase-3 detected by immunohistochemistry and western blotting, and the ratios of Bcl-2/Bax were decreased. Our results suggest that nobiletin has significant inhibitory effects on hepatocellular carcinoma both in vitro and in vivo. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A series of new crosslinked copoly(urethane-methacrylate)s (CPUAs) were synthesized by the polymerization of new urethane-methacrylate macromonomers with double bonds at the end of the chain, which were prepared from isophorone diisocyanate, β-hydroxyethyl methacrylate, different content of poly(1,2-propanediol ortho-phthalate) (PPP), and poly(ethylene glycol) 600. The properties of CPUAs were measured by dynamic mechanical analysis, thermogravimetric analysis, wide-angle X-ray diffraction, water uptake, and optical properties testing, and mechanical performance measurements. The results revealed that the greater PPP contents in the CPUAs lead to the higher glass transition temperature, hardness, lower thermal stability, and water uptake. Obtained CPUAs present the good transparence. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Hand mouthing (HM) is a chronic problem in many individuals with intellectual disabilities. Although the prevalence of mouthing has been estimated, data on the frequency, severity, or functions of the behavior were not included. In Study 1, we examined the prevalence and risk of HM. Results obtained from interviews showed that the prevalence of HM in two institutional samples (N = 802) was 12.7%, whereas direct observation yielded a lower estimate of prevalence (8%). Moreover, a large proportion of observed HM (39.1%) was self-injurious in nature. In Study 2, we used modified functional analyses (FAs) to examine the HM of 64 individuals. Results indicated that maintenance by automatic reinforcement accounted for 98.4% of the cases (all but one case). In Study 3, we implemented a progressive series of interventions for HM exhibited by 14 individuals. The following interventions were implemented in sequential order: (a) noncontingent reinforcement (NCR, effective with 6 subjects), (b) either NCR plus differential reinforcement of alternative behavior (DRA) plus response blocking (effective with 5 subjects) or NCR plus response blocking only (effective with 2 subjects), and (c) NCR plus brief manual restraint (effective with 1 subject). [ABSTRACT FROM AUTHOR]

Well-dispersed multiwalled carbon nanotubes/polyurethane (MWCNTs/PU) composites were synthesized in situ polymerization based on treating MWCNTs with nitric acid and silane coupling agent. The morphology and degree of dispersion of the MWCNTs were studied using a high resolution transmission electron microscopy (HR-TEM) and X-ray powder diffraction (XRD). The result showed that MWCNTs could be dispersed still in the PU matrix well with the addition of 2 wt% MWCNTs. The thermal and mechanical properties of the composites were characterized by dynamic mechanical thermal analysis, thermogravimetric analysis, tensile, and impact testing. The result suggested that the glass transition temperature ( Tg) of composites increased greatly with increasing MWCNTs content slightly, and the MWCNTs is also helpful to improve mechanical properties of composites. Furthermore, the composites have an excellent mechanical property with the addition of 0.5 wt% MWCNTs. The electrical property testing indicates that the MWCNTs can improve evidently the electrical properties of composites when adding 1 wt% MWCNTs to the PU matrix. The volume resistivity of composites reaches to an equilibrium value. POLYM. COMPOS., 33:1866-1873, 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Calcium, an ubiquitous second messenger, plays an essential and versatile role in cellular signaling. The diverse function of calcium signals is achieved by an excess of calcium sensors. Plants possess large numbers of calcium sensors, most of which have not been functionally characterized. To identify physiologically relevant calcium sensors in a specific cell type, we conducted a genome-wide functional survey in pollen tubes, for which spatiotemporal calcium signals are well-characterized and required for polarized tip growth. Pollen-specific members of calmodulin (CaM), CaM-like (CML), calcium-dependent protein kinase (CDPK) and calcineurin B-like protein (CBL) families were tagged with green fluorescence protein (GFP) and their localization patterns and overexpression phenotypes were characterized in tobacco pollen tubes. We found that several fusion proteins showed distinct overexpression phenotypes and subcellular localization patterns. CDPK24-GFP was localized to the vegetative nucleus and the generative cell/sperms. CDPK32-GFP caused severe growth depolarization. CBL2-GFP and CBL3-GFP exhibited dynamic patterns of subcellular localization, including several endomembrane compartments, the apical plasma membrane (PM), and cytoskeleton-like structures in pollen tubes. Their overexpression also inhibited pollen tube elongation and induced growth depolarization. These putative calcium sensors are excellent candidates for the calcium sensors responsible for the regulation of calcium homeostasis and calcium-dependent tip growth and growth oscillation in pollen tubes. [ABSTRACT FROM AUTHOR]

The article explores the synthesization of a series of novel crosslinked poly(urethane-methacrylate). Synthesization of low number average molecular weight unsaturated polyester containing hydroxyl groups was done with 1,2-propanediol,2-butyl-2-ethyl-1,3-propanediol and maleic anhydride. A series of prepolymers, which had double bonds at the chain's terminal, was prepared with dibutytin dilaurate used as catalyst.