Enzymatic Activation and Continuous Electrochemical Production of Methane from Dilute CO2 Sources with a Self-Healing Capsule.

Converting dilute CO2 source into value-added chemicals and fuels is a promising route to reduce fossil fuel consumption and greenhouse gas emission, but integrating electrocatalysis with CO2 capture still faced marked challenges. Herein, we show that a self-healing metal-organic macrocycle functionalized as an electrochemical catalyst to selectively produce methane from flue gas and air with the lowest applied potential so far (0.06 V vs reversible hydrogen electrode, RHE) through an enzymatic activation fashion. The capsule emulates the enzyme' pocket to abstract one in situ-formed CO2-adduct molecule with the commercial amino alcohols, forming an easy-to-reduce substrate-involving clathrate to combine the CO2 capture with electroreduction for a thorough CO2 reduction. We find that the self-healing system exhibited enzymatic kinetics for the first time with the Michaelis-Menten mechanism in the electrochemical reduction of CO2 and maintained a methane Faraday efficiency (FE) of 74.24% with a selectivity of over 99% for continuous operation over 200 h. A consecutive working lab at 50 mA·cm-2, in an eleven-for-one (10 h working and 1 h healing) electrolysis manner, gives a methane turnover number (TON) of more than 10,000 within 100 h. The integrated electrolysis with CO2 capture facilitates the thorough reduction of flue gas (ca. 13.0% of CO2) and first time of air (ca. 400 ppm of CO2 to 42.7 mL CH4 from 1.0 m3 air). The new self-healing strategy of molecular electrocatalyst with an enzymatic activation manner and anodic shifting of the applied potentials provided a departure from the existing electrochemical catalytic techniques.

Functional coupling between MC4R and Kir7.1 contributes to clozapine-induced hyperphagia.

Most antipsychotic drugs (APDs) induce hyperphagia and weight gain. However, the neural mechanisms are poorly understood, partly due to challenges replicating their metabolic effects in rodents. Here, we report a new mouse model that recapitulates overeating induced by clozapine, a widely prescribed APD. Our study shows that clozapine boosts food intake by inhibiting melanocortin 4 receptor (MC4R) expressing neurons in the paraventricular nucleus of the hypothalamus. Interestingly, neither clozapine nor risperidone, another commonly used APD, affects receptor-ligand binding or the canonical Gαs signaling of MC4R. Instead, they inhibit neuronal activity by enhancing the coupling between MC4R and Kir7.1, leading to the open state of the inwardly rectifying potassium channel. Deletion of Kir7.1 in Mc4r-Cre neurons prevents clozapine-induced weight gain, while treatment with a selective Kir7.1 blocker mitigates overeating in clozapine-fed mice. Our findings unveil a molecular pathway underlying the effect of APDs on feeding behavior and suggest its potential as a therapeutic target.

Engineering NH2-Cu-NH2 Triple-atom Sites in Defective MOFs for Selective Overall Photoreduction of CO2 into CH3COCH3.

Selective photoreduction of CO2 to multicarbon products, is an important but challenging task, due to high CO2 activation barriers and insufficient catalytic sites for C-C coupling. Herein, a defect engineering strategy for incorporating copper sites into the connected nodes of defective metal-organic framework UiO-66-NH2 for selective overall photo-reduction of CO2 into acetone. The Cu2+ site in well-modified CuN2O2 units served as a trapping site to capture electrons via efficient electron-hole separation, forming the active Cu+ site for CO2 reduction. Two NH2 groups in CuN2O2 unit adsorb CO2 and cooperated with copper ion to functionalize as a triple atom catalytic site, each interacting with one CO2 molecule to strengthen the binding of *CO intermediate to the catalytic site. The deoxygenated *CO attached to the Cu site interacted with *CH3 fixed at one amino group to form the key intermediate CO*-CH3, which interacted with the third reduction intermediate on another amino group to produce acetone. Our photocatalyst realizes efficient overall CO2 reduction to C3 product acetone CH3COCH3 with an evolution rate of 70.9 µmol gcat -1 h-1 and a selectivity up to 97 % without any adducts, offering a promising avenue for designing triple-atomic sites to producing C3 product from photosynthesis with water.

Highly birefringent side-hole fiber Bragg grating for high-temperature pressure sensing.

We demonstrate a novel, to the best of our knowledge, high-temperature pressure sensor based on a highly birefringent fiber Bragg grating (Hi-Bi FBG) fabricated in a dual side-hole fiber (DSHF). The Hi-Bi FBG is generated by a femtosecond laser directly written sawtooth structure in the DSHF cladding along the fiber core through the slow axis (i.e., the direction perpendicular to the dual-hole axis). The sawtooth structure serves as an in-fiber stressor and also generates Bragg resonance due to its periodicity. The DSHF was etched by hydrofluoric acid to increase its pressure sensitivity, and the diameter of two air holes was enlarged from 38.2 to 49.6 µm. A Hi-Bi FBG with a birefringence of up to 1.8 × 10-3 was successfully created in the etched DSHF. Two distinct reflection peaks could be observed by using a commercial FBG interrogator. Moreover, pressure measurement from 0 to 3 MPa at a high temperature of 700°C was conducted by monitoring the birefringence-induced peak splits and achieved a high-pressure sensitivity of -21.2 pm/MPa. The discrimination of the temperature and pressure could be realized by simultaneously measuring the Bragg wavelength shifts and peak splits. Furthermore, a wavelength-division-multiplexed (WDM) Hi-Bi FBG array was also constructed in the DSHF and was used for quasi-distributed high-pressure sensing up to 3 MPa. As such, the proposed femtosecond laser-inscribed Hi-Bi FBG is a promising tool for high-temperature pressure sensing in harsh environments, such as aerospace vehicles, nuclear reactors, and petrochemical industries.

Sample enrichment for single-nucleus sequencing using concanavalin A-conjugated magnetic beads.

Single-cell/nucleus sequencing has been increasingly used to study specific cell populations. However, cells/nuclei often become diluted during isolation steps and are difficult to reconcentrate through centrifugation. Here, we present a protocol for sample enrichment using concanavalin A-conjugated magnetic beads. We describe steps for dissection, nuclei isolation, and fluorescence-activated cell sorting (FACS). We then detail procedures for nuclei enrichment and library preparation. This protocol enables efficient retrieval and enrichment of cells/nuclei following FACS and integrates into existing workflows of various 10× Genomics applications.

Homophilic interaction of cell adhesion molecule 3 coordinates retina neuroepithelial cell proliferation.

Correct cell number generation is central to tissue development. However, in vivo roles of coordinated proliferation of individual neural progenitors in regulating cell numbers of developing neural tissues and the underlying molecular mechanism remain mostly elusive. Here, we showed that wild-type (WT) donor retinal progenitor cells (RPCs) generated significantly expanded clones in host retinae with G1-lengthening by p15 (cdkn2a/b) overexpression (p15+) in zebrafish. Further analysis showed that cell adhesion molecule 3 (cadm3) was reduced in p15+ host retinae, and overexpression of either full-length or ectodomains of Cadm3 in p15+ host retinae markedly suppressed the clonal expansion of WT donor RPCs. Notably, WT donor RPCs in retinae with cadm3 disruption recapitulated expanded clones that were found in p15+ retinae. More strikingly, overexpression of Cadm3 without extracellular ig1 domain in RPCs resulted in expanded clones and increased retinal total cell number. Thus, homophilic interaction of Cadm3 provides an intercellular mechanism underlying coordinated cell proliferation to ensure cell number homeostasis of the developing neuroepithelia.

Melanocortin 4 receptor signaling in Sim1 neurons permits sexual receptivity in female mice.

Introduction: Female sexual dysfunction affects approximately 40% of women in the United States, yet few therapeutic options exist for these patients. The melanocortin system is a new treatment target for hypoactive sexual desire disorder (HSDD), but the neuronal pathways involved are unclear. Methods: In this study, the sexual behavior of female MC4R knockout mice lacking melanocortin 4 receptors (MC4Rs) was examined. The mice were then bred to express MC4Rs exclusively on Sim1 neurons (tbMC4RSim1 mice) or on oxytocin neurons (tbMC4ROxt mice) to examine the effect on sexual responsiveness. Results: MC4R knockout mice were found to approach males less and have reduced receptivity to copulation, as indicated by a low lordosis quotient. These changes were independent of body weight. Lordosis behavior was normalized in tbMC4RSim1 mice and improved in tbMC4ROxt mice. In contrast, approach behavior was unchanged in tbMC4RSim1 mice but greatly increased in tbMC4ROxt animals. The changes were independent of melanocortin-driven metabolic effects. Discussion: These results implicate MC4R signaling in Oxt neurons in appetitive behaviors and MC4R signaling in Sim1 neurons in female sexual receptivity, while suggesting melanocortin-driven sexual function does not rely on metabolic neural circuits.

Nuclear receptor 5A2 regulation of Agrp underlies olanzapine-induced hyperphagia.

Antipsychotic (AP) drugs are efficacious treatments for various psychiatric disorders, but excessive weight gain and subsequent development of metabolic disease remain serious side effects of their use. Increased food intake leads to AP-induced weight gain, but the underlying molecular mechanisms remain unknown. In previous studies, we identified the neuropeptide Agrp and the transcription factor nuclear receptor subfamily 5 group A member 2 (Nr5a2) as significantly upregulated genes in the hypothalamus following AP-induced hyperphagia. While Agrp is expressed specifically in the arcuate nucleus of the hypothalamus and plays a critical role in appetite stimulation, Nr5a2 is expressed in both the CNS and periphery, but its role in food intake behaviors remains unknown. In this study, we investigated the role of hypothalamic Nr5a2 in AP-induced hyperphagia and weight gain. In hypothalamic cell lines, olanzapine treatment resulted in a dose-dependent increase in gene expression of Nr5a2 and Agrp. In mice, the pharmacological inhibition of NR5A2 decreased olanzapine-induced hyperphagia and weight gain, while the knockdown of Nr5a2 in the arcuate nucleus partially reversed olanzapine-induced hyperphagia. Chromatin-immunoprecipitation studies showed for the first time that NR5A2 directly binds to the Agrp promoter region. Lastly, the analysis of single-cell RNA seq data confirms that Nr5a2 and Agrp are co-expressed in a subset of neurons in the arcuate nucleus. In summary, we identify Nr5a2 as a key mechanistic driver of AP-induced food intake. These findings can inform future clinical development of APs that do not activate hyperphagia and weight gain.

Orthogonal single-mode helical Bragg gratings created in fiber cladding for vector bending measurement.

We demonstrate a novel, to the best of our knowledge, two-dimensional vector bending sensor based on orthogonal helical Bragg gratings inscribed in the cladding of a conventional single-mode fiber (SMF). The helical cladding fiber Bragg gratings (HCFBGs) are created by using a femtosecond laser direct writing technology and a quarter-pitch graded index fiber (GIF) is used in front of the HCFBGs to diverge the core mode into fiber cladding. In contrast to the multimode resonance observed in conventional cladding Bragg gratings inscribed by using a femtosecond laser point-by-point (PbP) or line-by-line (LbL) technology, the proposed HCFBGs exhibit stable narrowband single-mode Bragg resonance. An HCFBG with a low peak reflectivity of -50.77 dB and a narrow bandwidth of 0.66 nm was successfully fabricated by using a lateral offset of 45 µm between the HCFBG and the fiber core axis. Moreover, two orthogonal HCFBGs were fabricated in the SMF cladding and used for vector bending sensing. Strong orientation dependence could be seen in omnidirectional bending measurement, exhibiting a maximum bending sensitivity of up to 50.0 pm/m-1, which is comparable to that in a multicore FBG. In addition, both the orientation and amplitude of bending vector could be reconstructed by using the measured Bragg wavelength shifts in two orthogonal HCFBGs. As such, the proposed HCFBGs could be used in many applications, such as structural health monitoring, robotic arms, and medical instruments.

Simultaneous measurement of torsion and strain at high temperature by using a highly birefringent cladding fiber Bragg grating.

We demonstrate the fabrication of a new highly birefringent cladding fiber Bragg grating (Hi-Bi CFBG) consisting of a pair of sawtooth stressors near the fiber core by using a femtosecond laser direct writing technology. The unique sawtooth structure serves as in-fiber stressor and also generates Bragg resonance due to its periodicity. After optimization of laser pulse energy, the Hi-Bi CFBG with a high birefringence of 2.2 × 10-4 and a low peak reflectivity of ∼ -24.5 dB (corresponding to ∼ 0.3%) was successfully fabricated in a conventional single-mode fiber (SMF). And then, a wavelength-division-multiplexed Hi-Bi CFBGs array and an identical Hi-Bi CFBGs array were successfully constructed. Moreover, a simultaneous measurement of torsion and strain at high temperature of 700 °C was realized by using the fabricated Hi-Bi CFBG, in which the torsion can be deduced by monitoring the reflection difference between the two polarization peaks and strain can be detected by measuring polarization peak wavelength. A high torsion sensitivity of up to 80.02 dB/(deg/mm) and a strain sensitivity of 1.06 pm/µÉ› were achieved. As such, the proposed Hi-Bi CFBG can be used as a mechanical sensor in many areas, especially in structural health monitoring at extreme conditions.

A clinical practice guideline for the screening and assessment of enthesitis in patients with spondyloarthritis.

Objective: The aim of this review is to provide guidance on the selection of approaches to the screening and assessment of enthesitis in patients with spondyloarthritis (SpA). Methods: Twenty-four questions regarding the approaches to the screening and assessment of enthesitis and the implementation details were devised, followed by a systemic literature review. The Grading of Recommendations Assessment, Development, and Evaluation methodology was employed in the development of this guideline, with modifications to evaluate non-interventional approaches under comprehensive consideration of costs, accessibility, and evidence strength. A consensus from the voting panel was required for the inclusion of the final recommendations and the strength of each recommendation. Results: Seventeen recommendations (including five strong recommendations) were included in this guideline. The voting panel expressed unequivocal support for the necessity of screening and assessment of enthesitis in patients with SpA. It was agreed unanimously that symptom evaluation and physical examination should serve as the initial steps to the recognition of enthesitis, whereas Maastricht Ankylosing Spondylitis Enthesitis Score is a reliable tool in both clinical trials and daily medical practice. Ultrasound examination is another reliable tool, with power Doppler ultrasound as an informative addition. Notwithstanding its high resolution, MRI is limited by the costs and relatively low accessibility, whereas radiographs had low sensitivity and therefore should be rendered obsolete in the assessment of enthesitis. PET/CT was strongly opposed in the detection of enthesitis. Conclusion: This guideline provides clinicians with information regarding the screening and assessment of enthesitis in patients with SpA. However, this guideline does not intend on dictating choices, and the ultimate decisions should be made in light of the actual circumstances of the facilities.

Jag2b-Notch3/1b-mediated neuron-to-glia crosstalk controls retinal gliogenesis.

In the developing central nervous systems (CNS), neural progenitor cells generate neurons and glia in sequential order. However, the influence of neurons on glia generation remains elusive. Here, we report that photoreceptor cell-derived Jag2b is required for Notch-dependent Müller glia (MG) generation in the developing zebrafish retina. In jab2b-/- mutants, differentiating MGs are re-specified into lineage-related bipolar neuron fate at the expense of mature MG. Single-cell transcriptome analysis and knock-in animals reveal that jab2b is specifically expressed in crx+ -photoreceptor cells during MG generation. Crx promoter-driven jag2b, but not other Notch ligands, is sufficient to rescue the loss of MGs observed in jag2b-/- mutants. Furthermore, we observe a severe and moderate decrease in the number of MGs in notch3-/- and notch1b-/- mutants, respectively, and the activation of Notch3 or Notch1b rescues the MG loss in jag2b-/- mutants. Together, our findings reveal that the interaction of Jag2b and Notch3/Notch1b mediates the crosstalk between neurons and glial cells to ensure the irreversible differentiation of MG, providing novel mechanistic insights into the temporal specification of glial cell fate in a developing vertebrate CNS structure.

Delineating a serotonin 1B receptor circuit for appetite suppression in mice.

Triptans are a class of commonly prescribed antimigraine drugs. Here, we report a previously unrecognized role for them to suppress appetite in mice. In particular, frovatriptan treatment reduces food intake and body weight in diet-induced obese mice. Moreover, the anorectic effect depends on the serotonin (5-HT) 1B receptor (Htr1b). By ablating Htr1b in four different brain regions, we demonstrate that Htr1b engages in spatiotemporally segregated neural pathways to regulate postnatal growth and food intake. Moreover, Htr1b in AgRP neurons in the arcuate nucleus of the hypothalamus (ARH) contributes to the hypophagic effects of HTR1B agonists. To further study the anorexigenic Htr1b circuit, we generated Htr1b-Cre mice. We find that ARH Htr1b neurons bidirectionally regulate food intake in vivo. Furthermore, single-nucleus RNA sequencing analyses revealed that Htr1b marks a subset of AgRP neurons. Finally, we used an intersectional approach to specifically target these neurons (Htr1bAgRP neurons). We show that they regulate food intake, in part, through a Htr1bAgRP→PVH circuit.

Quasi-Distributed Temperature and Strain Sensors Based on Series-Integrated Fiber Bragg Gratings.

Two types of series-integrated fiber Bragg gratings (SI-FBGs), i.e., strong and weak SI-FBGs, were inscribed in a standard single-mode fiber (SMF) using the femtosecond laser point-by-point technology. In the SI-FBGs inscribing system, the grating pitch of each FBG and the distance between the two adjacent FBGs in the SI-FBGs can be flexibly controlled by adjusting the inscription parameters. The strong SI-FBGs with different grating pitches and the weak SI-FBGs with an identical grating pitch were employed to successfully measure the temperature distribution in a tube furnace and the strain distribution on a cantilever beam, respectively. A high spatial resolution of less than 1 mm was achieved during the distributed temperature sensing experiment. Moreover, the spatial resolution could be improved by decreasing the distance between the two adjacent FBGs, i.e., decreasing the FBG length and the space between the two adjacent FBGs. Hence, the inscribed high-quality SI-FBGs have great potential to be developed as various quasi-distributed sensors with a high spatial resolution.

Stabilized Ultra-High-Temperature Sensors Based on Inert Gas-Sealed Sapphire Fiber Bragg Gratings.

In situ measurement of high temperature is critical in aerospace, petrochemical, metallurgical, and power industries. The single-crystal sapphire fiber is a promising material for high-temperature measurement owing to its high melting point of ∼2045 °C. Sapphire fiber Bragg gratings (SFBGs), which could be inscribed in sapphire fibers with a femtosecond laser, are widely used as high-temperature sensors. However, conventional SFBGs typically exhibit a significant deterioration in their spectra after long-term operation at ultra-high temperatures, resulting from the formation of some unwanted microstructural features, that is, lossy spots and micro-etched lines, on the surface of the sapphire fiber. Here, we report for the first time, to the best of our knowledge, a thermally stabilized ultra-high-temperature sensor based on an SFBG created by femtosecond laser inscription, inert gas-sealed packaging, and gradient temperature-elevated annealing. The results indicate that the lossy spots are essentially aluminum hydroxide induced by high-temperature oxidation, and the inert gas-sealed packaging process can effectively insulate the sapphire fiber from the ambient air. Moreover, the formation of micro-etched lines was suppressed successfully by using the gradient temperature-elevated annealing process. As a result, the surface topography of the SFBG after operating at high temperatures was improved obviously. The long-term thermal stability of such an SFBG was greatly enhanced, showing a stable operation at 1600 °C for up to 20 h. In addition, it could withstand an even higher temperature of 1800 °C with a sensitivity of 41.2 pm/°C. The aforementioned results make it promising for high-temperature sensing in chemical, aviation, smelting, and power industries.

Femtosecond laser auto-positioning direct writing of a multicore fiber Bragg grating array for shape sensing.

A multicore fiber Bragg grating (MC-FBG) array shape sensor is a powerful tool for a variety of applications. However, the efficient fabrication of high-quality MC-FBG arrays remains a problem. Here, we report for the first time, to the best of our knowledge, a new method of directly writing FBG arrays in a seven-core fiber (SCF) through the protective coating using femtosecond laser auto-positioning point-by-point technology, which is accomplished by image recognition and micro-displacement compensation. An MC-FBG array consisting of 140 individual FBGs with a grating length of 2 mm was successfully inscribed into seven cores of a 440 mm-long SCF. Each core contained 20 wavelength-division-multiplexed (WDM) FBGs with wavelengths ranging from 1522.11 nm to 1579.28 nm. In other words, the MC-FBG array consisted of 20 WDM nodes with an interval of 2 cm along the fiber, and each node contained seven identical FBGs integrated in parallel into the fiber cross-section. Moreover, the fabricated MC-FBG array exhibited a strong orientation dependence in bend sensing, with a maximum sensitivity of 55.49 pm/m-1. Subsequently, 2D and 3D shape sensing were demonstrated using the fabricated MC-FBG array, with maximum reconstruction errors per unit length of 4.51% and 10.81%, respectively. Hence, the MC-FBG arrays fabricated using the proposed method are useful in many applications, such as posture monitoring, smart robotics, and minimally invasive surgery.

Femtosecond laser line-by-line inscription of apodized fiber Bragg gratings.

The reflection spectra of conventional fiber Bragg gratings (FBGs) with uniform index modulation profiles typically have strong sidelobes, which hamper the performance of FBG-based optical filters, fiber lasers, and sensors. Here, we propose and demonstrate a femtosecond laser line-by-line (LbL) scanning technique for fabricating apodized FBGs with suppressed sidelobes. This approach can flexibly achieve various apodized modulation profiles via precise control over the length and/or transverse position of each laser-inscribed index modification track. We theoretically and experimentally studied the influences of the apodization function on the side-mode suppression ratio (SMSR) in the fabricated apodized FBG, and the results show that a maximum SMSR of 20.6 dB was achieved in a Gaussian-apodized FBG. Subsequently, we used this method to fabricate various apodized FBGs, and the SMSRs in these FBGs were reduced effectively. Specifically, a dense-wavelength-division-multiplexed Gaussian-apodized FBG array with a wavelength interval of 1.50 nm was successfully fabricated, and the SMSR in such an array is 14 dB. Moreover, a Gaussian-apodized phase-shifted FBG and chirped FBG were also demonstrated with a high SMSR of 14 and 16 dB, respectively. Therefore, such an apodization method based on a modified femtosecond laser LbL scanning technique is an effective and flexible way to fabricate various FBGs with high SMSRs, which is promising to improve the performance of optical filters, fiber lasers, and sensors.

Femtosecond laser point-by-point inscription of an ultra-weak fiber Bragg grating array for distributed high-temperature sensing.

Ultra-weak fiber Bragg grating (UWFBG) arrays are key elements for constructing large-scale quasi-distributed sensing networks for structural health monitoring. Conventional methods for creating UWFBG arrays are based on in-line UV exposure during fiber drawing. However, the UV-induced UWFBG arrays cannot withstand a high temperature above 450 °C. Here, we report for the first time, to the best of our knowledge, a new method for fabricating high-temperature-resistant UWFBG arrays by using a femtosecond laser point-by-point (PbP) technology. UWFBGs with a low peak reflectivity of ∼ - 45 dB (corresponding to ∼ 0.0032%) were successfully fabricated in a conventional single-mode fiber (SMF) by femtosecond laser PbP inscription through fiber coating. Moreover, the influences of grating length, laser pulse energy, and grating order on the UWFBGs were studied, and a grating length of 1 mm, a pulse energy of 29.2 nJ, and a grating order of 120 were used for fabricating the UWFBGs. And then, a long-term high-temperature annealing was carried out, and the results show that the UWFBGs can withstand a high temperature of 1000 °C and have an excellent thermal repeatability with a sensitivity of 18.2 pm/°C at 1000 °C. A UWFBG array consisting of 200 identical UWFBGs was successfully fabricated along a 2 m-long conventional SMF with an interval of 10 mm, and interrogated with an optical frequency domain reflectometer (OFDR). Distributed high-temperature sensing up to 1000 °C was demonstrated by using the fabricated UWFBG array and OFDR demodulation. As such, the proposed femtosecond laser-inscribed UWFBG array is promising for distributed high-temperature sensing in hash environments, such as aerospace vehicles, nuclear plants, and smelting furnaces.

Organophosphonate-Functionalized Telluromolybdate Containing a [TeMo10O37]10- Building Block and Its Catalytic Efficiency for Knoevenagel Condensation.

A novel organodiphosphonate-based telluromolybdate cluster, (NH4)6Na3H13[TeMo10O37(CoMo2O6L)4]·11H2O [1; L = (O3P)2C(O)(CH2)3NH2], has been successfully synthesized by a simple one-pot aqueous reaction. Intriguingly, the [TeMo10O37]10- subunit with tetrahedral geometry of TeO4 is observed in the organophosphonate-functionalized polyoxometalates for the first time. Compound 1 was prepared in a buffer solution (pH = 5.5) with alendronic acid (Ale) and (NH4)6Mo7O24·4H2O as raw materials. The polyanion [TeMo10O37(CoMo2O6L)4]22- was constructed from four {Mo2O6L} subunits encapsulating an interesting Te-Mo heterometal subunit [TeMo10O37]10- through four CoO6 octahedra and has been fully characterized by routine techniques. In addition, compound 1, as a heterogeneous catalyst, shows good conversion (92%) and high selectivity (99%) for Knoevenagel condensation reaction.