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Objective: The long-term impact of COVID-19 on patient health has been a recent focus. This study aims to determine the persistent symptoms and psychological conditions of patients hospitalized with COVID-19 15 months after onset, that patients first developed symptoms. The potential risk factors were also explored. Methods: A cohort of COVID-19 patients discharged from February 20, 2020 to March 31, 2020 was recruited. Follow-ups were conducted using validated questionnaires and psychological screening scales at 15 months after onset to evaluate the patients' health status. The risk factors for long-term health impacts and their associations with disease severity was analyzed. Findings: 534 COVID-19 patients were enrolled. The median age of the patients was 62.0 years old (IQR 52.0-70.0) and 295 were female (55.2%). The median time from onset to follow-up was 460.0 (451.0-467.0) days. Sleep disturbance (18.5%, 99/534) and fatigue (17.2%, 92/534) were the most common persistent symptoms. 6.4% (34/534) of the patients had depression, 9.2% (49/534) were anxious, 13.0% (70/534) had insomnia and 4.7% (25/534) suffered from post-traumatic stress disorder (PTSD). Multivariate adjusted logistic regression analysis showed that glucocorticoid use during hospitalization (OR 3.58, 95% CI 1.12-11.44) was significantly associated with an increased risk of fatigue. The OR values for anxiety and sleep disorders were 2.36 (95% CI 1.07-5.20) and 2.16 (95% CI 1.13-4.14) in females to males. The OR value of PTSD was 25.6 (95% CI 3.3-198.4) in patients with persistent symptoms to those without persistent symptoms. No significant associations were observed between fatigue syndrome or adverse mental outcomes and disease severity. Conclusions: 15-month follow-up in this study demonstrated the need of extended rehabilitation intervention for complete recovery in COVID-19 patients.
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PURPOSE: We aim to present unsupervised machine learning-based analysis of clinical features, bone mineral density (BMD) features, and medical care costs of Rotator cuff tears (RCT). PATIENTS AND METHODS: Fifty-three patients with RCT were reviewed, the clinical features, BMD features, and medical care costs were collected and analyzed by descriptive statistics. Furtherly, unsupervised machine learning (UML) algorithm was used for dimensionality reduction and cluster analysis of the RCT data. RESULTS: There were 26 males and 27 females. The patients were divided into four subgroups using the UML algorithm. There were significant differences among four subgroups regarding trauma exposure, full-thickness supraspinatus tendon tears, infraspinatus tendon tear, subscapularis tendon tear, BMD distribution, medial row anchors, lateral row anchors, total medical care costs, and consumables costs. We observed the highest frequency of trauma exposure, infraspinatus tendon tear, subscapularis tendon tear, osteoporosis, the highest number of medial row anchors, lateral row anchors, total medical care costs, and consumables costs in subgroup II. CONCLUSION: The unsupervised machine learning-based analysis of RCT can provide clinically meaningful classification, which shows good interpretability and contribute to a better understanding of RCT. The significance of the results is limited due to the small number of samples, a larger follow-up study is needed to confirm the encouraging results.
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The purpose of the study was to investigate the relationship between postoperative bone marrow lesions (BMLs) and pain severity in patients undergoing open wedge high tibial osteotomy (OWHTO). We reviewed the patients undergoing OWHTO between April 2018 and April 2020. The demographic and clinical data of patients were collected. Clinically, VAS and Knee injury and Osteoarthritis Outcome Score (KOOS) were used to assess pain level and functional outcomes of patients. The MRI Osteoarthritis Knee Score (MOAKS) was used to assess the total BMLs size in medial tibiofemoral (MTF), lateral tibiofemoral (LTF), and patellofemoral (PF) joints. 98 patients were enrolled in the study, including 57 male and 41 female patients. The VAS scores improved significantly from 6.1 ± 0.8 to 1.5 ± 0.9 (p < 0.001), and all subscales of KOOS improved significantly after surgery (p < 0.001). There were no significant differences between the pre- and postoperative total BML size of PF and LTF joints (p > 0.05). We observed significant improvements in the total BML size of MTF joint (p < 0.001). The VAS scores and KOOS pain scores improved better in patients without postoperative MTF joint BMLs (p < 0.001). Postoperative MTF joint BMLs were correlated with postoperative VAS (p < 0.001) and KOOS pain (p < 0.001). Our study demonstrates that MTF joint BMLs improved significantly after OWTHO. We confirmed that the presence of postoperative MTF joint BMLs are strongly associated with pain severity. The greater the improvement in postoperative MTF joint BMLs, the less pain. Our findings provide valuable understandings of OWHTO in the treatment of knee osteoarthritis (KOA) and potential future directions for KOA treatment approaches.
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Medula Óssea/patologia , Osteotomia/efeitos adversos , Medição da Dor , Índice de Gravidade de Doença , Tíbia/cirurgia , Idoso , Medula Óssea/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Período Pós-Operatório , Tíbia/diagnóstico por imagem , Resultado do Tratamento , Escala Visual AnalógicaRESUMO
BACKGROUND: To verify the differential expression of miR-30c and miR-142-3p between tuberculosis patients and healthy controls and to investigate the performance of microRNA (miRNA) and subsequently models for the diagnosis of tuberculosis (TB). METHODS: We followed up 460 subjects suspected of TB, and finally enrolled 132 patients, including 60 TB patients, 24 non-TB disease controls (TB-DCs), and 48 healthy controls (HCs). The differential expression of miR-30c and miR-142-3p in serum samples of the TB patients, TB-DCs, and HCs were identified by reverse transcription-quantitative real-time PCR. Diagnostic models were developed by analyzing the characteristics of miRNA and electronic health records (EHRs). These models evaluated by the area under the curves (AUC) and calibration curves were presented as nomograms. RESULTS: There were differential expression of miR-30c and miR-142-3p between TB patients and HCs (p < 0.05). Individual miRNA has a limited diagnostic value for TB. However, diagnostic performance has been both significantly improved when we integrated miR-142-3p and ordinary EHRs to develop two models for the diagnosis of tuberculosis. The AUC of the model for distinguishing tuberculosis patients from healthy controls has increased from 0.75 (95% CI: 0.66-0.84) to 0.96 (95% CI: 0.92-0.99) and the model for distinguishing tuberculosis patients from non-TB disease controls has increased from 0.67 (95% CI: 0.55-0.79) to 0.94 (95% CI: 0.89-0.99). CONCLUSIONS: Integrating serum miR-142-3p and EHRs is a good strategy for improving TB diagnosis.
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Registros Eletrônicos de Saúde , MicroRNAs/sangue , Nomogramas , Tuberculose/diagnóstico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROCRESUMO
PURPOSE: We aim to present an unsupervised machine learning application in anterior cruciate ligament (ACL) rupture and evaluate whether supervised machine learning-derived radiomics features enable prediction of ACL rupture accurately. PATIENTS AND METHODS: Sixty-eight patients were reviewed. Their demographic features were recorded, radiomics features were extracted, and the input dataset was defined as a collection of demographic features and radiomics features. The input dataset was automatically classified by the unsupervised machine learning algorithm. Then, we used a supervised machine learning algorithm to construct a radiomics model. The t-test and least absolute shrinkage and selection operator (LASSO) method were used for feature selection, random forest and support vector machine (SVM) were used as machine learning classifiers. For each model, the sensitivity, specificity, accuracy, and the area under the curve (AUC) of receiver operating characteristic (ROC) curves were calculated to evaluate model performance. RESULTS: In total, 5 demographic features were recorded and 106 radiomics features were extracted. By applying the unsupervised machine learning algorithm, patients were divided into 5 groups. Group 5 had the highest incidence of ACL rupture and left knee involvement. There were significant differences in left knee involvement among the groups. Forty-three radiomics features were extracted using t-test and 7 radiomics features were extracted using LASSO method. We found that the combination of LASSO selection method and random forest classifier has the highest sensitivity, specificity, accuracy, and AUC. The 7 radiomics features extracted by LASSO method were potential predictors for ACL rupture. CONCLUSION: We validated the clinical application of unsupervised machine learning involving ACL rupture. Moreover, we found 7 radiomics features which were potential predictors for ACL rupture. The study indicated that radiomics could be a valuable method in the prediction of ACL rupture.
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The hierarchical aggregation of molecular nanostructures from multiple components is a grand synthetic challenge, which requires highly selective linkage control. We demonstrate how two orthogonal linkage groups, that is, organotin and lanthanide cations, can be used to drive the aggregation of a giant molecular metal oxide superstructure. The title compound {[(Sn(CH3 )2 )2 O]4 {[CeW5 O18 ] [TeW4 O16 ][CeSn(CH3 )2 ]4 [TeW8 O31 ]4 }2 }46- (1 a) features dimensions of ca. 2.2×2.3×3.4â nm3 and a molecular weight of ca. 25â kDa. Structural analysis shows the hierarchical aggregation from several independent subunits. Initial biomedical tests show that 1 features an inhibitory effect on the proliferation of HeLa cells based on an apoptosis pathway. Inâ vivo experiments in mice reveal the antiproliferative activity of 1 and open new paths for further development of this new compound class.
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Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Tungstênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Tungstênio/químicaRESUMO
PURPOSE: The purpose of this study was to investigate the periodontal status in adult periodontal disease patients with malocclusion treated with digital clear aligners. METHODS: Thirty-three patients with periodontal disease who needed orthodontic treatment were selected. The patients were randomly divided into 2 groups, digital clear aligners group (experimental group, 16 patients) and fixed appliances group (control group, 17 patients). Bleeding index (BI), probing depth(PD), plaque index(PLI) and gingival index(GI) were recorded at baseline and 1, 3, 6 and 9 months during orthodontic treatment. SPSS 17.0 software package was used to analyze and compare the data of periodontal status between two groups. RESULTS: 1, 3, 6, and 9 months after orthodontic treatment, clinical parameters of the control group were significantly higher than baseline(P<0.05). The same measurements of the experimental group showed no significant differences at 1, 3, 6, and 9 months of treatment (P>0.05). After 1, 3, 6, and 9 months of treatment, the clinical parameters of BI, PLI and GI in the experimental group were significantly lower than the control group(P<0.05); PD in the experimental group was smaller than the control group, but there was no significant difference(P>0.05). CONCLUSIONS: Compared with conventional fixed appliance, clear aligner of digitalization can more effectively maintain periodontal heath in adult periodontal disease patients with malocclusion.
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Má Oclusão , Aparelhos Ortodônticos Removíveis , Doenças Periodontais , Adulto , Índice de Placa Dentária , Humanos , Má Oclusão/terapia , Doenças Periodontais/terapia , Índice PeriodontalRESUMO
Tuberculosis (TB) is one of the most common infectious diseases globally. The surfactant protein C (SFTPC), which is involved in innate immunity and surfactant function in the lung, may contribute toward the progression of TB. The aim of the present study was to preliminarily investigate the possible association of single nucleotide polymorphisms (SNPs) in the SFTPC gene with TB susceptibility and clinical phenotypes in a Western Chinese Han population. The improved multiplex ligation detection reaction method was used to genotype 6 SNPs in SFTPC, in 900 patients with TB and 1,534 healthy control subjects. It was found that the A allele for rs1124 and the C allele for rs8192313 were associated with increased susceptibility to TB, P=0.024 and P=0.045, respectively. However, these two P-values were not significant following Bonferroni correction. In all samples, the haplotype [CGA], representing three SFTPC variants, was revealed to increase the risk of TB (P=0.001 and P=0.005, following Bonferroni correction). Furthermore, patients with the AA genotype for rs1124 and with the CC genotype for rs8192313 were associated with higher levels of C-reactive protein (P=0.001 and P=0.005, respectively). The results of the present study indicated that the SFTPC SNPs may increase the susceptibility to TB and the immune response of the host to Mycobacterium tuberculosis and may potentially be novel biomarkers for the pathogenesis of TB.
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Rapid and accurate diagnosis of multidrug-resistant tuberculosis (MDR-TB) is important for timely and appropriate therapy. In this study, a rapid and easy-to-perform molecular test that integrated polymerase chain reaction (PCR) amplification and a specific 96-well microplate hybridization assay, called PCR-ELISA (enzyme-linked immunosorbent assay), were developed for detection of mutations in rpoB, katG, and inhA genes responsible for rifampin (RIF) and isoniazid (INH) resistance and prediction of drug susceptibility in Mycobacterium tuberculosis clinical isolates. We evaluated the utility of this method by using 32 multidrug-resistent (MDR) isolates and 22 susceptible isolates; subsequently, we compared the results with data obtained by conventional drug susceptibility testing and DNA sequencing. The sensitivity and specificity of the PCR-ELISA test were 93.7% and 100% for detecting RIF resistance, and 87.5% and 100% for detecting INH resistance, respectively. These results were comparable to those yielded by commercially available molecular tests such as the GenoType MTBDRplus assay. Based on the aforementioned results, we conclude that the PCR-ELISA microplate hybridization assay is a rapid, inexpensive, convenient, and reliable test that will be useful for rapid diagnosis of MDR-TB, for improved clinical care.
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Ensaio de Imunoadsorção Enzimática , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Farmacorresistência Bacteriana Múltipla , Genótipo , Técnicas de Genotipagem , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Diagnóstico Molecular/métodos , Mutação , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológicoRESUMO
Mast cells play a significant role in urticaria pathogenesis. It's evidenced that vitamin D has positive impact in chronic spontaneous urticaria (CSU) recently, but underlying mechanisms remain unclear. In this study, isobaric tag for relative and absolute quantification-liquid chromatography-mass spectrometer/mass spectrometer was used to detect the expression of proteins in sera of CSU patients and healthy subjects. Thirty-one differentially expressed proteins were identified, in which vitamin D binding protein (VDBP) was higher in CSU patients than that in healthy subjects after verification. Our results indicated that sera of CSU patients induced the production of vascular endothelial growth factor (VEGF) in mast cells through PI3K/Akt/p38 MAPK/HIF-1α axis in an IgE-depended way, and 25(OH)D3 suppressed the expression of VEGF by inhibiting this signaling pathway axis in this process. Collectively, these results suggest VDBP to be a potential biomarker and propose a potential mechanism of benefit for vitamin D therapy in CSU.
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Urticária Crônica/tratamento farmacológico , Urticária Crônica/metabolismo , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Crescimento do Endotélio Vascular/metabolismo , Vitamina D/farmacologia , Adulto , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imunoglobulina E/metabolismo , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
A family of penta-rare-earth incorporated tetravacant Dawson selenotungstates [H2 N(CH3 )2 ]10 H3 [SeO4 RE5 (H2 O)7 (Se2 W14 O52 )2 ] â 40H2 O [RE=Ho3+ (1), Er3+ (2), Tm3+ (3), Tb3+ (4)] were synthesized. It should be noted that a penta-RE [SeO4 RE5 (H2 O)7 ]11+ central core connecting two tetra-vacant Dawson-type [Se2 W14 O52 ]12- subunits generates a dimeric assembly of [SeO4 RE5 (H2 O)7 (Se2 W14 O52 )2 ]13- in the structures of 1-4. Meanwhile, a class of Ho3+ /Tm3+ co-doped derivatives based on 1 with a Ho3+ /Tm3+ molar ratio of 0.75:0.25-0.25:0.75 were also prepared and characterized by energy-dispersive spectroscopy (EDS) analyses. Moreover, their luminescence properties were systematically investigated, which indicate that Tm3+ ions can sensitize the emission of Ho3+ ions in the visible region and prolong the fluorescence lifetime of Ho3+ ions to some extent. Energy transfer from Tm3+ ions to Ho3+ ions was probed by time-resolved emission spectroscopy (TRES), and the CIE 1931 diagram has been applied to evaluate all possible luminescence colors.
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The etiology of urticaria is heterogeneous and allergic responses may be involved in it. The aim of the present study was to investigate the prevalence and distribution of sensitivity to inhaled and food allergens among patients with urticaria in Henan province (China). The levels of specific immunoglobulin E (sIgE) were detected using the AllergyScreen test and a total of 524/1,091 cases (48.0%) tested positive for sIgE to at least one of the 19 allergens. The most common inhaled allergens the urticaria patients were sensitive to were D. pteronyssinus (34.5%), cockroach (12.5%) and tree pollen mix (11.1%), while the food allergens with the highest rate of allergic reactions were cashew nut (8.1%), shrimp (6.8%) and crab (6.4%). The positive rates for D. pteronyssinus, dog hair, cockroach, mold mix, tree pollen mix and shrimp in the chronic urticaria group were higher than those in the acute urticaria group (P<0.05). Furthermore, positive rates for the majority of allergens were higher in males than in females and were significantly different between age groups (P<0.05). The results of the present study provided information on the characteristics of allergen sensitization of patients with urticaria and may facilitate the prevention, diagnosis and management of urticaria in Henan province.
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New chalcone-based pyridinium salts have been successfully exploited, which could smoothly participate in the highly diastereoselective dearomatization with binucleophilic enaminones by taking advantage of their multiple reactive sites to construct bibridged benzoazepines in up to 89% yields. The key to the success was the skillful and unprecedented C-3 functionalization of the new pyridinium salts. This work not only provides a kind of novel pyridinium salt synthon but also achieves the first C-3 functionalization of pyridinium salts to construct complex and challenging bibridged benzoazepines with high synthetic efficiency.
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A family of inorganic-organic hybrid one-dimensional (1-D) chain iron-lanthanide (Ln) heterometal encapsulated tungstotellurates [H2N(CH3)2]8K2Na4[Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2][Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]·50H2O [Ln = Eu3+ (1), Tb3+ (2), Dy3+ (3), Er3+ (4), HAc = acetate acid, H2pdca = 2,5-pyridinedicarboxylic acid] were prepared using a facile "one-pot" reaction. The molecular structures of 1-4 consist of an intriguing organic-ligand-connecting Fe-Ln heterometal inserted tetrameric unit [Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2][Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]14-. Appealingly, the tetrameric unit is composed of two sandwich-type subunits [Ln2(Ac)2(H2O)4Fe2(Hpdca)2(B-ß-TeW9O33)2]8- and [Ln2(H2O)8Fe2(Hpdca)2(B-ß-TeW9O33)2]6-, in which each sandwich-type subunit can be regarded as a derivative of two Ln-organic complexes substituting two external FeIII ions in the classic Krebs-type [Fe4(H2O)10(ß-TeW9O33)2]4- fragment. Furthermore, adjacent tetrameric units are interconnected into a 1-D chain arrangement by Hpdca- bridges. 1-4 represent the first examples of Fe-Ln heterometal encapsulated tungstotellurates. Comprehensive magnetic measurements of 3 imply the possible single-molecule magnet properties in 3 with an estimated relaxation time τ0 ≈ 6.06 × 10-6 s at Hdc = 0 Oe and τ0 ≈ 6.97 × 10-5 s at Hdc = 1500 Oe. In addition, the solid-state photoluminescence spectra of 1 and 2 at room temperature exhibit the typical f-f transitions of Ln cations. The Commission International d'Eclairage (CIE) color coordinates of (0.540â¯24, 0.442â¯44) for 1 and (0.428â¯71, 0.428â¯30) for 2 along with the correlated color temperatures of 1995 and 3278 K, dominant wavelengths of 586 and 578 nm, and color purities of 95.09% and 57.27% for 1 and 2 are obtained.
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Two multi-Ce3+-substituted selenotungstates (STs), [HDMEA][H2N(CH3)2]4H3Na4[Ce2(H2O)6(DMEA)W4O9(α-SeW9O33)3]·26H2O (1) and [H2N(CH3)2]10H4Na10[Ce2W4O9(H2O)7(α-SeW9O33)3]2·63H2O (2), were prepared by the one-pot approach of sodium tungstate, sodium selenite, and lanthanide nitrate in an acidic water solution in the presence of N, N-dimethylethanolamine (DMEA) or dimethylamine hydrochloride (DMAHC). 1 was obained in the presence of DMEA, whereas 2 was synthesized in the presence of DMAHC. The trimeric polyoxoanion of 1 contains an unusual V-shaped [Se3W29O103]20- group embracing a prominent heterometal oxide fragment, [Ce2(H2O)6(DMEA)W2O5]8+, and the hexameric polyoxoanion of 2 is constructed from two equivalent trimeric [Ce2W4O9(H2O)7(SeW9O33)3]224- subunits through two -O-W-O-Ce-O- linkages. The most worthy of attention is that the polyoxoanion of 1 can be approximatively viewed as a half of the polyoxoanion of 2 because of the coordination and blocking effect of DMEA. The stability of 1 and 2 in different water pH values was studied by electrospray ionization mass spectroscopy (ESI-MS), and the results manifest that 1 and 2 are stable in pH = 3.5-7.5 and 3.5-7.0, respectively. The oxidation reactions of aromatic sulfides catalyzed by H2O2 were studied when 1 or 2 worked as a catalyst, and experimental results reveal that 1 or 2 can serve as available catalysts for the oxidation of aromatic sulfides under mild conditions.
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On the basis of the synergistic strategy of lacunary polyoxometalate structure-directing function and chiral ligand inducting role, two pairs of enantiomeric polyoxotungstates, (NH4)4(TMA)4[Zr4(µ3-O)2(l-/d-mal)2(B-α-HSiW10O37)2] (TMA = tetramethylammonium, mal = malate (C4H5O5); l-mal for 1a, d-mal for 1b) and (NH4)4(TMA)4[Zr4(µ3-O)2(l-/d-mal)2(B-α-PW10O37)2] (l-mal for 2a, d-mal for 2b), and a mesomeric polyoxotungstate, (NH4)3Na2K5[Zr4(µ3-O)2(l-mal)(d-mal)(B-α-SiW10O37)2] (3), were hydrothermally synthesized. 1a, 2a and 1b, 2b respectively exhibit 1-D 21 right- and left-hand helical chains formed by hydrogen-bonding interactions, and 3 forms a 3-D (3,10)-connected framework by Na+/K+ ions with {418.624.83}{43}2 topology. These homochiral compounds represent the first examples of enantiomerically pure ZrIV-substituted Keggin POMs. In this system, {Zr4(µ3-O)2(l-/d-mal)2} clusters transfer chirality from d- or l-mal to Keggin polyoxotungstate dimeric clusters, which was demonstrated by structural comparison between the homochiral architecture and mesomer as well as circular dichroism spectra of enantiomers. UV-vis diffuse reflectance spectra reveal that 1-3 are potential semiconductor materials. In addition, 1 and 2 exhibit second harmonic generation response with their response intensities of 0.8 times that of KDP.
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During the past decade, isopolyoxotungstates (iso-POTs) and their derivatives have been greatly developed due to their unique structures and potential applications in luminescence, magnetism, catalysis etc. This brief review is principally focused on the main research progress on iso-POTs, iso-POT-based transition-metal derivatives, iso-POT-based rare-earth derivatives, iso-POT-based organometallic derivatives and iso-POT-based heterometallic derivatives, and gives a summary of some representative examples of their syntheses, structures and related properties. In addition, an outlook on the future of this area is presented in the final section. We believe that this systematic commentary on iso-POTs and their derivatives will not only disclose a rich set of iso-POT structures, but also reveal a more promising direction for the further functionalization of iso-POTs.
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The facile one-step assembly reaction of Na2WO4·2H2O, Sn(CH3)2Cl2, RE(NO3)3·6H2O and K2TeO3 in the presence of dimethylamine hydrochloride as an organic solubilizing agent in acidic aqueous solution resulted in a family of dimethyltin-functionalized rare-earth (RE) incorporated tellurotungstates consisting of {B-α-TeW7O28} and {W5O18} mixed building units [H2N(CH3)2]8Na4H2[RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]2·18H2O [RE = ErIII (1), YbIII (2), HoIII (3), YIII (4)]. The most striking structural characteristic of 1-4 is that they all contain a novel tetrameric S-shaped [RE2(OH)(B-α-TeW7O28)Sn2(CH3)4(W5O18)]214- moiety simultaneously including two pentavacant Keggin [B-α-TeW7O28]12- and two monovacant Lindqvist [W5O18]6- fragments connected by RE and dimethyltin linkers. To the best of our knowledge, such dimethyltin-functionalized RE-containing tellurotungstates have not been reported before. The visible or NIR solid-state emission spectra of 1 and 3 display the characteristic emission bands arising from ErIII and HoIII centers. Moreover, various 1-Er/Yb co-doped samples were prepared by controlling different mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O in the range of 0.96:0.04-0.02:0.98. In the visible region, the emission intensity of the 1-Er0.40/Yb0.60 co-doped sample reaches the maximum at the mass ratio of Er(NO3)3·6H2O/Yb(NO3)·6H2O being 0.40:0.60, and this observation is mainly derived from the fact that the Yb3+ ions can sensitize the Er3+ ions to enhance the emission intensity in the visible region. However, no such phenomenon for the 1-Er/Yb co-doped samples is seen in the NIR region. Besides, the upconversion spectra of the 1-Er/Yb co-doped samples were first observed. In addition, the thermal stabilities of 1-4 were also investigated on the crystalline samples and the thermal decomposition process of 1 has been deeply studied.
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By virtue of combining an in-situ assembly process with a stepwise synthesis in conventional aqueous solution, two series of unique organic-inorganic hybrid heteropolyoxomolybdates were constructed from plenary Keggin germanomolybdates and Cu-Ln heterometallic units and fully characterized: [H2 INA]2 H8 [LnCu(INA)4 (H2 O)6 ]2 [α-GeMo12 O40 ]3 â 52 H2 O (Ln=La3+ (1), Ce3+ (2), Pr3+ (3), Nd3+ (4), Sm3+ (5), Eu3+ (6); HINA=isonicotinic acid) and (NH4 )[Cu(PA)2 ][Cu(PA)2 Ln(H2 O)8 ][α-GeMo12 O40 ]â 10 H2 O (Ln=Nd3+ (7), Sm3+ (8), Eu3+ (9); HPA=picolinic acid). The most remarkable structural characteristic of compounds 1-6 was that their molecular units were defined by three discrete plenary Keggin [α-GeMo12 O40 ]4- polyoxoanions and two organic-inorganic hybrid heterometallic [LnCu(INA)4 (H2 O)6 ]+ moieties, whereas compounds 7-9 exhibited a nice-looking 1D chain-like structure that was built from plenary [α-GeMo12 O40 ]4- polyoxoanions, pendent [Cu(PA)2 ] complexes, and bridging {[Cu(PA)2 ][Ln(H2 O)8 ]}3+ heterometallic groups. Notably, two different pyridine carboxylic acid ligands led to the discrepancy between the two structure types. To the best of our knowledge, compounds 1-9 constitute the first examples of plenary Keggin heterometallic germanomolybdates that include Cu-Ln-organic subunits. Further studies revealed that compounds 3 and 8 exhibited fast adsorption capacity for cationic dyes methylene blue (MB) and rhodamineâ B (RhB) in water. Moreover, compounds 3 and 8 could quickly and selectively adsorb MB from a mixture of MB/methyl orange (MO) or MB/azophloxine (Apo).