Investigation of copper sulfate pentahydrate dehydration by terahertz time-domain spectroscopy

Copper sulfate pentahydrate is investigated by terahertz time-domain spectroscopy. It is shown that the terahertz absorption coefficients are correlated with the particle size of the samples, as well as the heating rates of the ambient temperature. Furthermore, the water molecules of copper sulfate pentahydrate can be quantitatively characterized due to the high sensitivity of the terahertz wave to water molecules. Based on such results, the status of water incorporated in mineral opal is also characterized using terahertz time-domain spectroscopy. It indicates that terahertz technology can be considered as an efficient method to detect the dehydration of minerals.

Progress of electrochemical CO_(2)reduction reactions over polyoxometalate-based materials

Electrochemical CO_(2)reduction to value-added fuels and chemicals is recognized as a promising strategy to alleviate energy shortages and global warming owing to its high efficiency and economic feasibility.Recently,understanding the activity origin,selectivity regulation,and reaction mechanisms of CO_(2)reduction reactions(CO_(2)RRs)has become the focus of efficient electrocatalyst design.Polyoxometalates(POMs),a unique class of nanosized metal-oxo clusters,are promising candidates for the development of efficient CO_(2)RR electrocatalysts and,owing to their well-defined structure,remarkable electron/proton storage and transfer ability,and capacities for adsorption and activation of CO_(2),are ideal models for investigating the activity origin and reaction mechanisms of CO_(2)RR electrocatalysts.In this review,we focus on the activity origin and mechanism of CO_(2)RRs and survey recent advances that were achieved by employing POMs in electrocatalytic CO_(2)RRs.We highlight the significant roles of POMs in the electrocatalytic CO_(2)RR process and the main factors influencing selectivity regulation and catalytic CO_(2)RR performance,including the electrolyte,electron-transfer process,and surface characteristics.Finally,we offer a perspective of the advantages and future challenges of POM-based materials in electrocatalytic CO_(2)reduction that could inform new advancements in this promising research field.

Comparison between 4D robust optimization methods for carbon-ion treatment planning

Intensity-modulated particle therapy(IMPT)with carbon ions is comparatively susceptible to various uncertainties caused by breathing motion,including range,setup,and target positioning uncertainties.To determine relative biological effectiveness-weighted dose(RWD)distributions that are resilient to these uncertainties,the reference phase-based four-dimensional(4D)robust optimization(RP-4DRO)and each phase-based 4D robust optimization(EP-4DRO)method in carbon-ion IMPT treatment planning were evaluated and compared.Based on RWD distributions,4DRO methods were compared with 4D conventional optimization using planning target volume(PTV)margins(PTV-based optimization)to assess the effectiveness of the robust optimization methods.Carbon-ion IMPT treatment planning was conducted in a cohort of five lung cancer patients.The results indicated that the EP-4DRO method provided better robustness(P=0.080)and improved plan quality(P=0.225)for the clinical target volume(CTV)in the individual respiratory phase when compared with the PTV-based optimization.Compared with the PTV-based optimization,the RP-4DRO method ensured the robustness(P=0.022)of the dose distributions in the reference breathing phase,albeit with a slight sacrifice of the target coverage(P=0.450).Both 4DRO methods successfully maintained the doses delivered to the organs at risk(OARs)below tolerable levels,which were lower than the doses in the PTV-based optimization(P<0.05).Furthermore,the RP-4DRO method exhibited significantly superior performance when compared with the EP-4DRO method in enhancing overall OAR sparing in either the individual respiratory phase or reference respiratory phase(P<0.05).In general,both 4DRO methods outperformed the PTV-based optimization in terms of OAR sparing and robustness.

Terahertz Lens Fabricated by Natural Dolomite

Optical operations have served as the basis of spectroscopy and imaging in terahertz regimes for a long time.Available lenses are practical tools for modulations.We fabricate a kind of biconvex lens from the natural dolomite cluster.The lens works well at 0.1 THz based on the relatively high refractive index and low absorption coefficients.Compared with the lens fabricated by a dolomite stone,such a lens can focus dispersive terahertz beam efficiently in terahertz imaging systems,which indicates that natural minerals hold promising applications in terahertz optics.

Research progress on the correlation between ion channel and excitability of striatum neurons in Parkinson's disease

Parkinson's disease(PD)is a neurodegenerative disorder due to gradual loss of dopaminergic neurons in the substantia nigra in the midbrain,however the pathogenesis is unclear.There is a correlation between the excitability of striatal neurons and PD.Ion channels are important to maintain membrane potential and regulate excitability of neurons,while ionic mechanisms for modulation of neurons excitability are not fully understood.This article reviews the relationship between ion channels and excitability of striatal neurons in PD and ion channel changes in the pathogenesis of PD.In order to find new targets to treatment PD by intervening ion channels.

Development of Medication Literacy Scale for Pediatric Population with Nephrotic Syndrome and Assessment on Reliability and Validity

Objective:To develop a medication literacy scale for the pediatric population with nephrotic syndrome(NS)in order to evaluate its reliability and validity.Methods:According to the medication belief scale,specific medication beliefs,and self-set dimensions,the NS pediatric population health literacy scale was designed to evaluate the medication literacy of 120 children with NS.Items,homogeneity,reliability,and validity of the scale were analyzed.Results:There were statistically significant differences in the Levene F test between the top 27%and the last 27%of the 22 items(P<0.001).The differences in the t-test were statistically significant(P<0.001).Content validity I-CVI:after deletion of item 4,the I-CVI of other items were all higher than 0.91.S-CVI was higher than 0.80,and S-CVI/AVE was higher than 0.90.The internal consistency coefficient(Cronbach'sα)was 0.868.Structural validity:KMO(Kaiser-Meyer-Olkin)statistical value was 0.862,and Bartlett's spherical test value was 1578.172(P<0.001).The extracted 6 common factors explain 70.21%of the variance variation.The loads of 22 items on their main factors are all greater than 0.427 except items 2 and 5.Conclusion:The medication literacy scale for the NS pediatric population has proved its good practicability,but some items of cognition need to be further explored.

Mitochondrial transfer from bone-marrow-derived mesenchymal stromal cells to chondrocytes protects against cartilage degenerative mitochondrial dysfunction in rats chondrocytes

Background:Previous studies have reported that mitochondrial dysfunction participates in the pathological process of osteoarthritis(OA).However,studies that improve mitochondrial function are rare in OA.Mitochondrial transfer from mesenchymal stem cells(MSCs)to OA chondrocytes might be a cell-based therapy for the improvement of mitochondrial function to prevent cartilage degeneration.This study aimed to determine whether MSCs can donate mitochondria and protect the mitochondrial function and therefore reduce cartilage degeneration.Methods:Bone-marrow-derived mesenchymal stromal cells(BM-MSCs)were harvested from the marrow cavities of femurs and tibia in young rats.OA chondrocytes were gathered from the femoral and tibial plateau in old OA model rats.BM-MSCs and OA chondrocytes were co-cultured and mitochondrial transfer from BM-MSCs to chondrocytes was identified.Chondrocytes with mitochondria transferred from BM-MSCs were selected by fluorescence-activated cell sorting.Mitochondrial function of these cells,including mitochondrial membrane potential(Δψm),the activity of mitochondrial respiratory chain(MRC)enzymes,and adenosine triphosphate(ATP)content were quantified and compared to OA chondrocytes without mitochondrial transfer.Chondrocytes proliferation,apoptosis,and secretion ability were also analyzed between the two groups.Results:Mitochondrial transfer was found from BM-MSCs to OA chondrocytes.Chondrocytes with mitochondrial from MSCs(MSCs+OA group)showed increased mitochondrial membrane potential compared with OA chondrocytes without mitochondria transfer(OA group)(1.79±0.19 vs.0.71±0.12,t=10.42,P<0.0001).The activity of MRC enzymes,including MRC complex I,II,III,and citrate synthase was also improved(P<0.05).The content of ATP in MSCs+OA group was significantly higher than that in OA group(161.90±13.49 vs.87.62±11.07 nmol/mg,t=8.515,P<0.0001).Meanwhile,we observed decreased cell apoptosis(7.09%±0.68%vs.15.89%±1.30%,t=13.39,P<0.0001)and increased relative secretion of type II collagen(2.01±0.14 vs.1.06±0.11,t=9.141,P=0.0008)and proteoglycan protein(2.08±0.20 vs.0.97±0.12,t=8.227,P=0.0012)in MSCs+OA group,contrasted with OA group.Conclusions:Mitochondrial transfer from BM-MSCs provided protection for OA chondrocytes against mitochondrial dysfunction and degeneration through improving mitochondrial function,cell proliferation,and inhibiting apoptosis in chondrocytes.This finding may offer a new therapeutic direction for OA.

Effect of W on formation and properties of precipitates in Ni-based superalloys

The formation and properties of precipitates in wrought Ni-based superalloys with different W contents during long-term exposure to high temperatures were investigated.The scanning electron microscope,transmission electron microscope,and chemical phase analysis were used to investigate the formation and properties of precipitates.It is found that with increasing W content,the quantity and thermal stability of MC carbide in Ni-based superalloys increased,while the quantity of M_(23)C_(6)carbides decreased.As the results show,W has a higher partition coefficient in γ'-and γ-matrix,and the addition of W promotes the precipitation of γ'phase.W content has no significant effect on the morphology,size,crystal structure,and coarsening rate of γ'precipitates.The influence of W content on high-temperature tensile and creep properties of the alloys was investigated.The results showed that W content has no obvious influence on the high-temperature yield strength,but the elongation and area reduction decreased significantly when the addition of W was more than 4 wt.%.Because of the similar volume fractions of γ'phase,the creep fracture strengths in the tested alloys with lower W concentrations were not significantly different after long-term exposure at 700℃.

Conjugated organic component-functionalized hourglass-type phosphomolybdates for visible-light photocatalytic Cr(VI)reduction in wide pH range

Abstra ct Utilizing efficient and durable photocatalysts for the removal of carcinogen Cr(Ⅵ)in wide pH water environment is of great significance for environment remediation.Herein,three conjugated organic component-functionalized hourglass-type phosphomolybdate hybrids with the formulas(H_(2)DBQ)[Fe(-H_(2)O)_(3)]_(2){Fe[P_(4)Mo_(6)0_(31)H_(7)]_(2)}·7H_(2)O(1),(H_(2)DBQ)_(2)(H_(2)DBP)[Fe(H_(2)O)_(4)]{Fe[P_(4)Mo_(6)O_(31)H_(7)]_(2)}·4H_(2)O(2),(H_(2)DBP)_(2){Fe[P_(4-)Mo_(6)O_(31)H_(9)]_(2)}·10H_(2)O(3)(DBQ=2,2'-dimehyl-6,6'-biquinoline;DBP=4,4'-diaminobiphenyl)were synthesized via hydrothermal method as photocatalysts for reducing Cr(Ⅵ)under visible light illumination.Structure analysis showed that hybrids 1-3 consist of hourglass-type[Fe(P_(4)Mo_(6)O_(31)H_(6))_(2)]^(10)-(abbr.Fe{P_(4)Mo_(6)}_(2))poly anionic clusters functionalized with different proportional of conjugated organic components(DBQ and DBP)effectively regulated their visible-light absorption capabilities and electron structures,which could be employed to reflect the structure-activity relationship of materials.When used as catalysts for reducing Cr(Ⅵ),hybrids 1-3 displayed distinct photocatalytic activities with Cr(Ⅵ)removal efficiencies of 91%,86%and 81%with only 10 W of white light being used as illumination,which are superior to that of pristine Fe{P_(4)Mo_(6)}_(2) salt(62%).Moreover,hybrid 1 also maintained high Cr(Ⅵ)removal efficiencies above~85%and high structural stabilities in solutions with wide pH ranges of2.5-10.0.Mechanism investigation showed that the higher organic component conjugation levels could promote the optic al absorption and facilitate the electron transfer between Fe{P_(4)Mo_(6)}_(2) and org anic components,thus resulting in effective Cr(Ⅵ)reduction photocatalytic efficacy.This work provides a viable way to design the photocatalysts based on polyoxometalates for removing wastewater pollutants.

The 2022 record-breaking high temperature in China:Sub-seasonal stepwise enhanced characteristics,possible causes and its predictability

In the summer of 2022,an unprecedented and long-lasting high temperature swept central-eastern China,causing significant societal effects.However,the sub-seasonal characteristics,causes and predictability of this extreme high temperature event are not well explored.Based on the locations,intensities and causes of the high temperature,we divided it into three stages:early(13 June-3 July),sustained(4-28 July),and enhancement(29 July-30 August)stages.The high temperature during the early stage mainly occurred in north-central China with an anomaly of 2.5℃compared with climatology(1981-2010),while the last two stages occurred in the middle and lower Yangtze River Basin with anomalies of 2.8 and 3.8℃respectively.The high temperature during the three stages were all regulated by the strengthening and westward extension of the western Pacific subtropical high(WPSH)but involved different physical process.In the early stage,it was mainly caused by the anticyclones over the Mongolia and Northwest Pacific and enhanced by the minor impact of WPSH.In the sustained stage it was influenced by relatively more stronger WPSH and South Asia high(SAH)and the relatively minor impact of the anticyclone over the north-western South Asia.In the enhancement stage,the high temperature was mainly caused by a combination of the record-breaking WPSH and SAH and the strong European blocking high.Inside,the exceptionally powerful WPSH was well correlated with the sea surface temperature gradient induced by the developing La Niña.The ECMWF and NCEP models reasonably predicted the location and intensity of the high temperature in the early stage,but poorly predicted that in the sustained and enhancement stages partly because of the failure prediction of the WPSH's enhancement and westward extension.The ECMWF model's more accurate prediction of the WPSH may contribute to its better forecasting of the heatwaves.

Polyoxometalate-encapsulated metal-organic frameworks with diverse cages for the C-H bond oxidation of alkylbenzenes

Exploring new heterogeneous catalysts to achieve efficient C-H bond oxidation is momentous in industrial chemical production.Herein,three Fe-incorporated polyoxometalate-encapsulated metal-organic frameworks(POM@MOFs),[Fe(H_(2)O)_(3)(dtb)][Fe(dtb)_(2)][HBW_(12)O_(40)]-12H_(2)O(1),[Fe(H_(2)O)2(dtb)]_(2)[Fe(dtb)_(2)(Hdtb)][SiW^(Ⅵ)_(9)W^(Ⅴ)_(3)O_(40)]·16H_(2)O(2),[Fe(H_(2)O)_(2)]_(4)(dtb)_(5)[PMo^(Ⅵ)_(11)Mo^(Ⅴ)O_(40)]_(2)·18H_(2)O(3),(dtb=1,4-di[4H-1,2,4-triazol-4-yl]-benzene),were hydrothermally synthesized for catalytic C-H bond oxidation.They exhibited three-dimensional(3-D)POM-based metal-organic host-guest frameworks with diverse cages.In compound 1,cationic metal-organic frameworks constructed by binuclear[Fe_(2)(dtb)_(6)(H_(2)O)_(2)]^(4+)clusters and dtb ligands present a pcu alpha-Po primitive cubic topological net and abundant twisted quadrangular prism-shaped cages,in which the monoprotonated[HBW_(12)O_(40)]^(4-)polyoxoanions are encapsulated.In compound 2,two-dimensional(2-D)cationic metal-organic layers constructed by trinuclear[Fe_(3)(dtb)_(6)(H_(2)O)_(4)]^(6+)clusters and dtb ligands display a sql/Shubnikov tetragonal plane net topology,in which the rhomboid-shaped metal-organic windows in adjacent parallel-arranged 2-D layers are enclosed to form an open parallelepiped cage.The[SiW^(Ⅵ)_(9)W^(Ⅴ)_(3)O_(40)]^(7-)poly-oxoanions locate in the parallelepiped cages between 2-D bilayers.In compound 3,the 3-D cationic metal-organic frameworks constructed by binuclear[Fe_(2)(dtb)_(3)(H_(2)O)_(4)]^(4+)clusters and dtb ligands possess a bnn hexagonal BN topology,in which the hexagonal prismatic metal-organic cages accommodate four[PMo^(Ⅵ)_(11)Mo^(Ⅴ)O_(40)]^(4-)poly-oxoanions.Employing diphenylmethane(DPM)oxidation as C-H bond oxidation model reaction,compounds 1-3 displayed distinct catalytic activities owing to the synergistic effect of polynuclear Fe nodes and poly-oxoanions.Among them,[PMo^(Ⅵ)_(11)Mo^(Ⅴ)O_(40)]^(4-)-contained compound 3 exhibited higher catalytic activity than polyoxotungstate-based compounds 1-2 with 99%DPM conversion and 99%benzophenone(BP)selectivity within 6 h as well as good recyclability and structural stability.

Boron heteroatom-doped silicon-carbon peanut-like composites enables long life lithium-ion batteries

Carbon coated Si core–shell structures have been proposed to solve the adverse effects of Si-based anode.However,designing ideal core–shell architecture with excellent surface and interface properties is still a significant challenge.Herein,a novel peanut-like structure of B-doped silicon/carbon nanoparticle(Si@B-C)synthe-sized by sol–gel process and subsequent thermal reduction is reported.The peanut-like Si@B-C electrode demon-strates a superior cyclability of 534 mAh·g^(-1)after 1000 cycles at high current density of 1000 mA·g^(-1).The exceptional electrochemical performance is attributed to the boric acid-induced highly interconnected peanut-like structure and boron heteroatom framework could provide a continuous electron pathway to reduce the irreversible lithium ion loss during rapid cycling.This work provides insight into the development of the heteroatom-doped Si-based anodes with stable cycling performance for LIBs.

Altered Retinal Dopamine Levels in a Melatonin-proficient Mouse Model of Form-deprivation Myopia

Reduced levels of retinal dopamine,a key regulator of eye development,are associated with experimental myopia in various species,but are not seen in the myopic eyes of C57BL/6 mice,which are deficient in melatonin,a neurohormone having extensive interactions with dopamine.Here,we examined the relationship between form-deprivation myopia(FDM)and retinal dopamine levels in melatonin-proficient CBA/CaJ mice.We found that these mice exhibited a myopic refractive shift in form-deprived eyes,which was accompanied by altered retinal dopamine levels.When melatonin receptors were pharmacologically blocked,FDM could still be induced,but its magnitude was reduced,and retinal dopamine levels were no longer altered in FDM animals,indicating that melatonin-related changes in retinal dopamine levels contribute to FDM.Thus,FDM is mediated by both dopamine level-independent and melatonin-related dopamine level-dependent mechanisms in CBA/CaJ mice.The previously reported unaltered retinal dopamine levels in myopic C57BL/6 mice may be attributed to melatonin deficiency.

Hydrogen bond-mediated polyoxometalate-based metal-organic networks for efficient and selective oxidation of aryl alkenes to aldehydes

Selective oxidation of aryl alkenes to aldehydes is an important approach to produce industrial raw materials,in which the exploration of an efficient heterogeneous catalyst is significant but challenging.In this work,three hydrogen bond-mediated polyoxometalate(POM)-contained metal–organic networks with the formulas of[Ni(BTD)2(H2O)2]2[SiW12O40]·12H2O(1),[Ni(BTD)2(H2O)]2[SiW12O40]·6H2O(2)and[Zn(BTD)2(H2O)]2[SiW12O40]·6H2O(3)(BTD=4H,4ʹH-[3,3ʹ-bi(1,2,4-triazole)]-5,5ʹ-diamine)were hydrothermally synthesized,in which the metal–organic fragments interact with POM clusters via abundant hydrogen bonding to extend the structure into three-dimensional supramolecular networks.To be explored as heterogenous catalysts,compounds 1–3 showed high catalytic activity and selectivity for the selective oxidation of styrene to benzaldehyde.Among them,compound 1 exhibits the highest performance with ca.99%styrene conversion and ca.99%selectivity of benzaldehyde in 5 h.Moreover,compound 1 displays rich substrate compatibility,recyclability and good structural stability.A series of experiments demonstrated that the high performance of compound 1 should be attributed to the synergistic effect among polyoxoanion and coordination-unsaturated metal centers in metal–organic fragments,which facilitates the activation of H2O2 and styrene substrates,thus enhancing the catalytic performance.

Cloning and Preliminary Characterization of Three Receptor-like Kinase Genes in Soybean

Leaf senescence that occurs in the last stage of leaf development is a genetically programmed process. It is very significant to isolate the upstream components in the senescence signaling pathway and to elucidate the molecular mechanisms that control the initiation and progression of leaf senescence. In this study, full-length cDNAs of three receptor-like protein kinase genes, designated rlpkl, rlpk2 and rlpk3, were cloned from artificially-induced senescent soybean （Glycine max L.） primary leaves （GenBank accession AY687390, AY687391, AF338813）. The deduced amino acid sequences indicated that they belonged to a receptor-like kinase family. Each of rlpkl and rlpk2 encodes a leucine-rich repeat （LRR） receptor-like protein kinase. They both comprise a typical signal peptide, several LRR motifs, a single-pass transmembrane domain, and a cytoplasmic protein kinase domain. No typical extracellular domain of RLPK3 was predicted. Organ-specific expression pattern analysis by reverse-transcription polymerase chain reaction （RT-PCR） revealed higher expression levels of the three genes in cotyledons, roots and flowers. Phylogenetic analysis indicated that RLPK1 and RLPK2 belonged to an independent branch, whereas RLPK3 shared common nodes with several known RLKs responding to ablotic and biotic stresses. The evident alternations of expression profiles of rlpkl and rlpk2 induced by the artificial senescence-inducing treatment implied involvements of these two RLKs in regulating soybean leaf senescence.

Prediction of freestanding semiconducting bilayer borophenes

Supported bilayerα-borophene(BL-αborophene)on Ag(111)substrate has been synthesized in recent experiments.Based on the experimentally observed quasi-planar C_(6v)B_(36)(1),its monolayer assemblyα^(+)-borophene B_(11)(P6/mmm)(2),and extensive global minimum searches augmented with density functional theory calculations,we predict herein freestanding BL-α^(+)borophenes B_(22)(Cmmm)(3)and B_(22)(C2/m)(4)which,as the most stable BL borophenes reported to date,are composed of interwoven boron triple chains as boron analogs of monolayer graphene(5)consisting of interwoven carbon single chains.The nearly degenerate eclipsed B_(22)(3)and staggered B_(22)(4)with the hexagonal hole density ofη=1/12 and interlayer bonding density of u=1/4 appear to be two-dimensional semiconductors with the indirect band gaps of 0.952 and 1.144 eV,respectively.Detailed bonding analyses reveal one delocalized 12c-2eπbond over each hexagonal hole in both the B_(22)(3)and B_(22)(4),similar to the situation in monolayer graphene which contains one delocalized 6c-2eπbond over each C_(6)hexagon.Furthermore,these BL-α^(+)borophenes appear to remain highly stable on Ag(111)substrate,presenting the possibility to form supported BL-α+borophenes.