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1.
IEEE Trans Image Process ; 33: 1574-1587, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38335089

RESUMO

Group activity recognition aims to identify a consistent group activity from different actions performed by respective individuals. Most existing methods focus on learning the interaction between each two individuals (i.e., second-order interaction). In this work, we argue that the second-order interactive relation is insufficient to address this task. We propose a third-order active factor graph network, which models the third-order interaction in each pair of three active individuals. At first, to alleviate the noisy individual actions, we select active individuals by measuring each individual's influence. The individuals with the top-k largest influence weights are selected as active individuals. Then, for each three-individuals pair, we build a new factor node and contact the factor node with these individual nodes. In other words, we extend the base second-order interactive graph to a new third-order interactive graph, which is defined as factor graph. Next, we design a two-branch factor graph network, in which one branch is to consider all individuals (denoted as full factor graph) and the other one takes the active individuals into consideration (denoted as active factor graph). We leverage both the active and full factor graphs comprehensively for group activity recognition. Besides, to enforce group consistency, a consistency-aware reasoning module is designed with two penalty terms, which describe the inconsistency between individual actions and group activity respectively. Extensive experiments demonstrate that our method achieves state-of-the-art performance on four benchmark datasets, i.e., Volleyball, Collective Activity, Collective Activity Extended, and SoccerNet-v3 datasets. Visualization results further validate the interpretability of our method.

2.
Materials (Basel) ; 14(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34683592

RESUMO

The construction of superhydrophobic surfaces necessitates the rational design of topographic surface structure and the reduction of surface energy. To date, the reported strategies are usually complex with multi-steps and costly. Thus, the simultaneous achievement of the two indispensable factors is highly desired, yet rather challenging. Herein, we develop a novel structure engineering strategy of realizing the fabrication of a functionally integrated device (FID) with a superhydrophobic surface via a one-step spraying method. Specifically, silica nanoparticles are used to control the surface roughness of the device, while polydimethylsiloxane is employed as the hydrophobic coating. Benefitting from the adopted superhydrophobicity, the as-fabricated FID exhibits a continuous, excellent oil-water separating performance (e.g., 92.5% separating efficiency) when coupled with a peristaltic pump. Notably, a smart design of incorporating a gas switch is adopted in this device, thereby effectively preventing water from entering the FID, realizing thorough oil collection, and avoiding secondary pollution. This work opens up an avenue for the design and development of the FID, accessible for rapid preparation and large-scale practical application.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1015893

RESUMO

FGFC1 (Fungi fibrinolytic compound1) is a bisindole compound with good biological activity, which was first derived from the Stachybotrys longispora FG216. However, the anti-tumor effects of FGFC1 have not been reported. This study investigated the effect and mechanism of FGFC1 on the proliferation, apoptosis, migration and invasion of non-small cell lung cancer (NSCLC) cells.Firstly, PC9, H1975, HCT116, HeLa and 293T cells were treated with different concentrations of FGFC1, and the cell counting kit-8 assay was used to determine relative cell viability; flow cytometry was used to evaluate apoptosis; real-time PCR and Western blotting analysis were performed to measure the expression of apoptosis-related genes in PC9 cells; wound healing and Transwell invasion assays were used to measure the ability of migration and invasion; Western blotting was performed to measure the expression of kinase proteins involved in the PI3K/Akt/mTOR signaling pathway, exploring the influence of FGFC1 on this signaling pathway. We found that FGFC1 selectively inhibited the proliferation of PC9 cells. It also up-regulated the expression of apoptosis-promoting protein cleaved-caspase-3 and cleaved-PARP, and induced apoptosis in a dose-dependent manner (P < 0. 05). FGFC1 also significantly inhibited the migratory and invasive capacity of PC9 cells in a dose-dependent manner (P < 0. 05). Further studies confirmed that FGFC1 could inhibit the activation of the PI3K/Akt/mTOR signaling pathway with the down-regulation of the protein expression levels of p-PI3K, p-Akt and p-mTOR. Thus, we conclude that FGFC1 inhibited the proliferation of PC9 and H1975 cells, induced the apoptosis and inhibited the migration and invasion of PC9 cells, which may take place through down-regulating the PI3K/Akt/mTOR signaling pathway. These findings suggest that FGFC1 might be a new therapeutic target in NSCLC treatment in the future.

4.
J Sci Food Agric ; 100(3): 936-944, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31487041

RESUMO

BACKGROUND: This study investigates the efficacy of short peptides secreted by Bacillus subtilis for fungal inhibition in fresh-cut pumpkin and for maintaining its shelf life. RESULTS: Low-molecular-weight filtrate (LC < 1000 Da) of B. subtilis culture (BC) significantly lowered the total number of molds on fresh-cut pumpkin compared with the untreated control and a BC group after storage. Low-molecular-weight filtrate prevented the deterioration of sensory quality in a pumpkin incision, and reduced pectinase activity. It also inhibited the growth of Phytophthora capsici and Penicillium chrysogenum, and the activity of ß-1,3-glucan synthase (GS) secreted by both molds. Fifty-seven GS-inhibiting peptides were screened from 95 LC peptides with two to five amino acid residues. The two most potent peptides, AWYW and HWWY, had strongly suppressive effects on the growth of P. capsici and P. chrysogenum. CONCLUSION: Our study demonstrated that short peptides present in B. subtilis culture can play an important role in the maintenance of fresh-cut pumpkin by suppressing fungal growth. © 2019 Society of Chemical Industry.


Assuntos
Bacillus subtilis/química , Cucurbita/microbiologia , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Peptídeos/farmacologia , Bacillus subtilis/metabolismo , Frutas/microbiologia , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Penicillium chrysogenum/efeitos dos fármacos , Penicillium chrysogenum/crescimento & desenvolvimento , Peptídeos/química , Peptídeos/metabolismo , Phytophthora/efeitos dos fármacos , Phytophthora/crescimento & desenvolvimento , Doenças das Plantas/microbiologia
5.
Chinese Journal of Stomatology ; (12): 599-603, 2018.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-810141

RESUMO

Objective@#To analyze factors affecting stability after fixed orthodontic treatment.@*Methods@#Five hundred and forty-four patients who had finished fixed orthodontic treatment more than two years in First Department of Orthodontics, China Medical University from January, 2000 to December, 2017 were investigated and the rate of regular revisit was counted. The data of 288 patients were successfully collected by calling or sending text messages and the rate of standard use of retainers as prescribed (patients wore retainers for 24 months or longer) was counted. According to the variation of peer assessment rating (PAR) index at the start of retention and the time the data collected, the patients were divided into relapse group (variation of PAR index >5) and non-relapse group (variation of PAR index ≤5). Difference significance analysis and multiple-factor logistic regression analysis were used. Sixty patients wearing retainers well were collected and the curative effects of Hawley retainer and vacuum formed retainer (VFR) were compared, which included overbite, overjet, maxillary irregularity index, mandibular irregularity index, width betwenn canine and width between first molar.@*Results@#The rate of regular revisit was 41.0% (223/544). Two hundred and one of 288 patients (69.8%) who were visited successfully had regular revisit, and 60.4%(174/288) of the patients wore retainers well; 30.2% (87/288) of the patients who were visited successfully didn't have regular revisit, and 10.4% (30/288) of the patients wore retainers well. Difference significance analysis showed that there was highly significant difference between relapse group and non-relapse group in the type of retainer and duration of retention (P<0.01). One hundred and forty of 224 patients (62.5%) in non-relapse group and 37.5% (24/64) of the patients in relapse group used VFR, and the duration of retention in non-relapse group was significantly longer than that in relapse group (P<0.01). Multiple-factor Logistic regression analysis showed that wearing Hawley retainers (OR=3.067, P<0.05) was the risk factor influencing relapse. The duration of retention (OR=0.832, P<0.01) was the protective factor influencing relapse. Independent-sample t test indicated that the variations of maxillary [(0.82±0.36) mm] and mandibular [(1.05±0.22) mm] irregularity index in Hawley retainer group were larger than maxillary [(0.64±0.29) mm] and mandibular [(0.72±0.35) mm)] irregularity index in VFR group, respectively. The differences between the two groups were significant (P<0.05).@*Conclusions@#Duration of retention was implicated in stability after orthodontic treatment. VFR had better effect in the aspects of irregularity index than Hawley retainer.

6.
BMC Pregnancy Childbirth ; 16(1): 189, 2016 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-27459998

RESUMO

BACKGROUND: Adiponectin is an adipocyte hormone involved in energy homeostasis and metabolism. However, its role in early infancy is poorly understood. METHODS: We recruited a total of 443 pregnant women and their children in this prospective study. Cord blood samples were successfully obtained from 331 neonates. Maternal and umbilical blood serum adiponectin were measured. The weight-, height- and BMI-for-age Z scores of infants at birth and at 3, 6 and 12 months of age were assessed. RESULTS: Multiple linear regression analysis indicated that cord blood but not maternal serum adiponectin was positively associated with all of the anthropometric measures at birth (P < 0.01). Using Generalized Estimating Equation model after adjustment for sex, time, maternal age, gestational age, prepregnancy BMI, weight gain during pregnancy, maternal education, parity, history of miscarriage and mode of delivery, for every 1-µg/ml increment of maternal serum adiponectin, the height-for-age Z score during the first year of life increased by 0.026 (P =0.013) on average, and the height-for-age Z score of infants in the highest quartile of maternal serum adiponectin was 0.270 (95 % CI: 0.013-0.527) higher than those in the lowest quartile. The changes in weight-for-age Z score from birth decreased by 0.67 × 10(-2) on average with every 1-µg/ml additional increase of cord blood adiponectin (P = 0.047). The infants in the highest quartile of cord blood adiponectin showed a -0.368 (95 % CI, -0.701--0.035) decrease in weight-for-age Z score change from birth compared with those in the lowest quartile. CONCLUSIONS: Cord blood adiponectin concentration is a determinant of infant birth size and weight gain in the first year of life. Circulating maternal adiponectin during pregnancy may predict postnatal height growth.


Assuntos
Adiponectina/sangue , Tamanho Corporal , Sangue Fetal/química , Trimestres da Gravidez/sangue , Adulto , Estatura , Índice de Massa Corporal , Peso Corporal , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Testes para Triagem do Soro Materno , Gravidez , Estudos Prospectivos
7.
Chinese Journal of Pathology ; (12): 366-371, 2013.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-233445

RESUMO

<p><b>OBJECTIVE</b>To investigate clinicopathological features of fibrous mass-forming chronic pancreatitis (FMCP), to compare clinicopathological and immunohistochemical characteristics between autoimmune pancreatitis (AIP) and fibrous mass-forming non-autoimmune pancreatitis (nAIP) and to provide evidence for pathological diagnosis, differential diagnosis and clinical treatment strategy.</p><p><b>METHODS</b>Clinicopathological features were analyzed in 81 cases of FMCP. Infiltrating IgG4(+) plasmacytes were counted by immunohistochemical staining.</p><p><b>RESULTS</b>Among 81 cases of FMCP, 20 cases were diagnosed as AIP and 61 cases were interpreted as nAIP. AIP was more common in males over 50 years, whereas nAIP was seen in much younger patients (P = 0.001). The amount of inflammatory cells in the stroma of AIPs was remarkable higher than that in nAIPs (P = 0.002). The incidence of neuritis in AIPs (100%, 20/20) was also higher compared with that of nAIPs (75.4%, 46/61; P = 0.017). Storiformed-fibrosis was more common in AIPs (95.0%, 19/20) than in nAIPs (1.6%, 1/61;P = 0.000). Pancreatic intraepithelial neoplasia (PanIN) was observed in 50.0%(10/20) of AIPs and 32.8%(20/61) of nAIPs, with a greater severity observed in AIPs (P = 0.031). Tubular complex (TC) was more commonly observed in AIPs (65.0%, 13/20) than nAIPs (26.2%, 16/61;P = 0.002). Among 81 cases of FMCP, 61 cases had less than 11 IgG4(+) plasmacytes /HPF, 7 cases had 10-30/HPF and 13 cases had over 30/HPF.</p><p><b>CONCLUSIONS</b>FMCPs include both AIP and nAIP. AIP has distinct pathological features and the presence of IgG4(+) plasmacyte is an important diagnostic parameter. FMCP appears to be an important precancerous lesion of pancreatic ductal adenocarcinoma. Surgery may be considered for patients with FMCP due to its mass-forming nature. In contrast, patients with AIP are treated medically due to its steroid-responsiveness. Therefore, accurate and timely diagnosis of AIP is of clinical relevance to avoid unnecessary surgical complications and to prevent progression of the disease.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Doenças Autoimunes , Alergia e Imunologia , Patologia , Cirurgia Geral , Carcinoma Ductal Pancreático , Alergia e Imunologia , Patologia , Cirurgia Geral , Diagnóstico Diferencial , Fibrose , Imunoglobulina G , Metabolismo , Pâncreas , Patologia , Neoplasias Pancreáticas , Alergia e Imunologia , Patologia , Cirurgia Geral , Pancreatite Crônica , Alergia e Imunologia , Patologia , Cirurgia Geral , Plasmócitos , Alergia e Imunologia , Lesões Pré-Cancerosas , Alergia e Imunologia , Patologia , Cirurgia Geral
8.
Orthop Surg ; 3(1): 64-71, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22009983

RESUMO

OBJECTIVE: To assess the clinical value of polymerase chain reaction (PCR) in the diagnosis and differential diagnosis of joint tuberculosis (TB). METHODS: PCR was used blindly to detect the DNA of Mycobacterium tuberculosis (M.TB) in five specimens of M.TB, 5 of BCG, and 10 of other bacteria. Then, M. TB in 98 samples from patients with joint TB and 100 samples from patients with non-tubercular joint disorders were detected by PCR, acid-fast staining and culture,. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PCR were calculated. The χ2 test was used for statistical analysis of the frequency of various factors. At the same time, some problems with PCR were also systematically analyzed. RESULTS: (1) In the "standard samples", both M. TB and BCG showed positive while other bacteria were negative. (2) In 98 cases from patients with joint TB, 81 were positive by PCR, 6 by acid-fast staining, and 17 by culture. In 100 cases from patients with non-tuberculous joint disorders, 9 were positive by PCR, and none by either acid-fast staining or culture. Sensitivity, specificity, accuracy, positive and negative predictive value of PCR were 82.65% (81/98), 91.00% (91/100), 86.87% (172/198), 90.00% (81/90) and 84.26% (91/108), respectively. (3) The positive rates for PCR, acid-fast staining and culture in detection of M. TB were 82.65% (81/98), 6.12% (6/98), and 17.34% (17/98), respectively. There were statistically significant differences between the three methods (P < 0.001). (4) The process of PCR is automatic, and can be completed within 3 to 6 hours, whereas 4 to 8 weeks are required for the conventional culture of M. TB. CONCLUSION: PCR is a sensitive, specific, rapid, simple and minimally invasive method for detection of M. TB in samples from joint TB, and can play an important role in early and rapid diagnosis and differential diagnosis of joint TB. But it also has some limitations, such as false positivity and false negativity.


Assuntos
DNA Bacteriano/análise , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Tuberculose Osteoarticular/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Diagnóstico Diferencial , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Valor Preditivo dos Testes , Sensibilidade e Especificidade
9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1404, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21588836

RESUMO

The asymmetric unit of the polymeric title compound, {[Zn(C(8)H(12)N(6))(H(2)O)(4)](C(14)H(8)O(4))}(n) or {[Zn(BTB)(H(2)O)(4)](BPDC)}(n) [BTB is 1,4-bis-(1,2,4-triazol-1-yl)butane and H(2)BPDC is biphenyl-4,4'-dicarb-oxy-lic acid], contains half a [Zn(BTB)(H(2)O)(4)](2+) cation and half a BPDC anion, both ions lying about a crystallographic inversion centre. The crystal structure consists of zigzag polymeric cationic chains parallel to the c axis and uncoordinated anions linked into a three-dimensional supra-molecular architecture by O-H⋯O, C-H⋯O hydrogen bonds and C-H⋯π inter-actions.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1405, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21588837

RESUMO

The title compound, [Cd(C(14)H(8)O(6)S)(H(2)O)(2)](n), comprises zigzag chains parallel to [111] of alternating [Cd(H(2)O)(2)](2+) and sulfonyl-dibenzoate units, with the Cd and S atoms lying on crystallographic twofold axes. The central Cd(II) ion is in a slightly distorted octa-hedral geometry, coordinated by six O atoms from two carboxyl-ate groups and two water O atoms. An intra-molecular C-H⋯O hydrogen bond occurs. In the crystal, inter-molecular hydrogen bonds between carboxyl-ate O atoms and coordinated water mol-ecules in adjacent chains lead to the formation of a three-dimensional network structure. The compound is isotypic with the Zn analog.

11.
Zhongguo Gu Shang ; 22(7): 504-6, 2009 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19705710

RESUMO

OBJECTIVE: To study the role of PCR technique in detection of mycobacterium tuberculosis in the samples from joint tuberculosis, and to evaluate the clinical value of PCR in diagnosis of joint tuberculosis. METHODS: From June 1993 to August 2001, PCR was used to detect DNA of mycobacterium tuberculosis, and the standard culture was applied to detect mycobacterium tuberculosis. Mycobacterium tuberculosis were respectively blindly by the two techniques in the samples obtained from 95 patients with joint tuberculosis (55 males and 40 females, the age ranging from 2 to 75 years, with an average of 34 years). The positive rate of mycobacterium tuberculosis detection was calculated. RESULTS: In the detection of mycobacterium tuberculosis, positive rate was 82% (78/95) in PCR technique, and 16% (15/95) in standard culture technique. There were statistical differences between the two groups (chi2=67, P<0.001). The whole process of PCR amplification was automatic and could be finished within several hours, and the detecting time was considerably shorter. CONCLUSION: PCR technique is a rapid, simple, sensitive and specific method for detection of mycobacterium tuberculosis in the samples of joint tuberculosis, showing more marked advantages than the standard culture technique. It is valuable in the early rapid diagnosis and differential diagnosis of joint tuberculosis.


Assuntos
Técnicas de Cultura/métodos , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Tuberculose Osteoarticular/diagnóstico , Adolescente , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Tuberculose Osteoarticular/microbiologia , Adulto Jovem
12.
World J Gastroenterol ; 13(17): 2484-9, 2007 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-17552033

RESUMO

AIM: To evaluate whether the combination of recombinant chicken fibroblast growth factor receptor-1 (FGFR-1) protein vaccine (cFR-1) combined with low-dose gemcitabine would improve anti-tumor efficacy in a mouse CT26 colon adenocarcinoma (CT26) model. METHODS: The CT26 model was established in BABL/c mice. Seven days after tumor cell injection, mice were randomly divided into four groups: combination therapy, cFR-1 alone, gemcitabine alone, and normal saline groups. Tumor growth, survival rate of tumor-bearing mice, and systemic toxicity were observed. The presence of anti-tumor auto-antibodies was detected by Western blot analysis and enzyme-linked immunospot assay, microvessel density (MVD) of the tumors and tumor cell proliferation were detected by Immunohistochemistry staining, and tumor cell apoptosis was detected by TdT-mediated biotinylated-dUTP nick end label staining. RESULTS: The combination therapy results in apparent decreases in tumor volume, microvessel density and tumor cell proliferation, and an increase in apoptosis without obvious side-effects as compared with either therapy alone or normal control groups. Also, both auto-antibodies and the antibody-producing B cells against mouse FGFR-1 were detected in mice immunized with cFR-1 vaccine alone or with combination therapy, but not in non-immunized mice. In addition, the deposition of auto-antibodies on endothelial cells from mice immunized with cFR-1 was observed by immunofluorescent stain-ing, but not on endothelial cells from control groups. Synergistic indexes of tumor volume, MVD, cell apoptosis and proliferation in the combination therapy group were 1.71 vs 1.15 vs 1.11 and 1.04, respectively, 31 d after tumor cell injection. CONCLUSION: The combination of cFR-1-mediated anti-angiogenesis and low-dose gemcitabine synergistically enhances the anti-tumor activity without overt toxicity in mice.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fator 1 de Crescimento de Fibroblastos/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Adenocarcinoma/irrigação sanguínea , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Vacinas Anticâncer/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Galinhas , Neoplasias do Colo/irrigação sanguínea , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Fator 1 de Crescimento de Fibroblastos/efeitos adversos , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Proteínas Recombinantes/efeitos adversos , Taxa de Sobrevida , Gencitabina
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-527947

RESUMO

Objective To investigate the influence of all-round intervention on the quality of life and the emotion of cancer patients who have accepted the gamma knife therapy. Method Using health education, psychotherapy and the behavior treatment for 260 patients with malignant tumor who had accepted the gamma knife therapy. Evaluated the quality of life and the emotion of these patients before and after the intervention respectively by using questionnaire of QOL, SCL-90, SDS and SAS. Results The values of indicated the QOL, SCL-90, SDS and SAS before the all-round intervention were 23.12?4.68, 68.12?33.26, 40.12?10.28 and 42.48?12.16 respectively. The values which had obtained after the all-round intervention were 46.26?3.28, 36.12?26.23, 28.16?5.23 and 26.12 ?10.66 respectively, there were significant differences between them,P

14.
Inorg Chem ; 44(10): 3664-8, 2005 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-15877450

RESUMO

Reactions of two preformed trinuclear W/Cu/S clusters, [A](2)[WS(4)(CuCN)(2)] (1: A = Et(4)N; 2: A = PPh(4)), with different concentrations of acetic acid in MeCN generate two interesting 2D polymeric clusters [Et(4)N](3)[(WS(4)Cu(2))(2)(mu-CN)(3)].2MeCN (3), and [PPh(4)][WS(4)Cu(3)(mu-CN)(2)].MeCN (4), respectively. Compound 4 can also be readily obtained in a high yield from the reaction of 2 with equimolar [Cu(MeCN)(4)]PF(6) in MeCN. These compounds have been characterized by elemental analysis, IR spectra, thermal analysis, and single-crystal X-ray diffraction. An X-ray analysis reveals that compound 3 retains the WS(4)Cu(2) cluster core, which serves as a 3-connecting node to link equivalent nodes via single cyanide bridges, forming an anionic 2D (6,3) net. Compound 4 consists of a T-shaped WS(4)Cu(3) core, which also acts as a 3-connecting node, with links to 3 equivalent clusters either through single or double cyanide bridges, affording a different anionic 2D (6,3) network. The acetic acid induced aggregation of 3 and 4 from the two cluster precursors 1 and 2 suggests that this simple synthetic strategy is likely to be applicable to many related systems.

15.
Acta Crystallogr C ; 59(Pt 11): m465-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14605392

RESUMO

The reaction of CuCN and KCN with (NH(4))(2)[WS(4)] followed by cation exchange with PPh(4)Br produced the title compound, (C(24)H(20)P)(2)[Cu(2)WS(4)(CN)(2)].CH(3)CN.H(2)O or (PPh(4))(2)[(NC)Cu(micro-S)(2)W(micro-S)(2)Cu(CN)].MeCN.H(2)O. In the structure of the dianion, [(NC)Cu(micro-S)(2)W(micro-S)(2)Cu(CN)](2-), the WS(4) moiety acts as a bidentate ligand that binds two CuCN groups, thus forming a slightly bent WCu(2) core with approximate D(2d) symmetry. The W-Cu distances are in the range 2.6463 (6)-2.6545 (6) A.

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