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The synthesis of a specific Sn plane as an efficient electrocatalyst for CO2 electrochemical reduction to generate fuels and chemicals is still a huge challenge. Density functional theory (DFT) calculations first reveal that the Sn(101) crystal plane is more advantageous for CO2 electroreduction. A metal-organic framework (MOF) precursor Sn-MOF has been carbonized and then etched to successfully fabricate Sn(101)/SnO2/C composites with good control of the carbonization time and the concentration of hydrochloric acid. The Sn(101) crystal plane of the catalyst could enhance the faradaic efficiency of formate to as high as 93.3% and catalytic stability up to 20 h. The promotion of the selectivity and activity by Sn(101) advances new possibilities for the rational design of high-activity Sn catalysts derived from MOFs.
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PURPOSE: Laparoscopic surgery is the standard surgical approach for colon cancer. However, there is no standard surgery for right colectomy. Selection between total laparoscopic right colectomy (TLRC) and laparoscopic-assisted right colectomy (LARC) is a topic of interest. In this systematic review, we compared the short-term outcomes of TLRC and LARC in the treatment of right colon cancer. METHODS: We identified studies (PubMed, Web of Science, Cochrane Library, Embase) comparing TLRC and LARC up to February 2021. Surgical duration; volume of intraoperative blood loss; number of harvested lymph nodes; incision length; hospitalization duration; time to first flatus; time to first defecation; and anastomotic leakage, ileus, and wound infection were compared. RESULTS: Thirty studies (TLRC, 1948 patients; LARC, 2369 patients) were evaluated. All studies were retrospective, except seven prospective studies, three RCTs, and three case-control studies. TLRC demonstrated lesser intraoperative blood loss volume (P < 0.01), less frequent intraoperative conversion to laparotomy (P = 0.02), shorter hospitalization duration (P < 0.01), smaller incision length (P < 0.01), shorter time to first flatus (P < 0.01) and first defecation (P < 0.01), and lesser frequent wound infection (P < 0.01) compared with LARC. The surgical duration, number of harvested lymph nodes, anastomotic leakage, and ileus were similar between TLRC and LARC (P > 0.05). CONCLUSION: TLRC is associated with significantly earlier bowel recovery, lesser blood loss, smaller incision length, lower rate of conversion, shorter hospitalization duration, and lesser frequent wound infection compared with LARC.
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Neoplasias do Colo , Laparoscopia , Anastomose Cirúrgica , Colectomia , Neoplasias do Colo/cirurgia , Humanos , Tempo de Internação , Duração da Cirurgia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The electrochemical reduction of CO2 presents a promising strategy to mitigate the greenhouse effect and reduce excess carbon dioxide emission to realize a carbon-neutral energy cycle, but it suffers from the lack of high-performance electrocatalysts. In this work, catalytic active cobalt porphyrin [TCPP(Co)=(5,10,15,20)-tetrakis(4-carboxyphenyl)porphyrin-CoII ] was precisely anchored onto water-stable 2D metal-organic framework (MOF) nanosheets (Zr-BTB) to obtain ultrathin 2D MOF nanosheets [TCPP(Co)/Zr-BTB] with accessible catalytic sites for the CO2 reduction reaction. Compared with molecular cobalt porphyrin, the TCPP(Co)/Zr-BTB exhibits an ultrahigh turnover frequency (TOF=4768â h-1 at -0.919â V vs. reversible hydrogen electrode, RHE) owing to high active-site utilization. In addition, three post-modified 2D MOF nanosheets [TCPP(Co)/Zr-BTB-PABA, TCPP(Co)/Zr-BTB-PSBA, TCPP(Co)/Zr-BTB-PSABA] were obtained, with the modifiers of p-(aminomethyl)benzoic acid (PABA), p-sulfobenzoic acid potassium (PSBA), and p-sulfamidobenzoic acid (PSABA), to change the micro-environments around TCPP(Co) through the tuning of steric effects. Among them, the TCPP(Co)/Zr-BTB-PSABA exhibited the best performance with a faradaic efficiency (FECO ) of 85.1 %, TOF of 5315â h-1 , and jtotal of 6â mA cm-2 at -0.769â V (vs. RHE). In addition, the long-term durability of the electrocatalysts is evaluated and the role of pH buffer is revealed.
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Separation of monophosphopeptides from multi-phosphopeptides in complex biological samples is significant in the study of protein kinase signal transduction pathways. To the best of our knowledge, very few materials have been reported that could selectively enrich monophosphopeptides because of the chemical difficulty in retaining the intermediate monophosphopeptides and excluding both non-phosphopeptides and multi-phosphopeptides in acidic conditions, which requires unique interactions to balance the metallic affinity and the hydrophobicity. With the large surface area, abundant accessible active sites, and ultrathin structures, two-dimensional (2-D) metal-organic framework (MOF) Hf-1,3,5-tris(4-carboxyphenyl)benzene (BTB) nanosheets were rationally selected. Due to the elongated organic ligands and the balance between metallic affinity of clusters and hydrophobicity from ligands, the 2-D Hf-BTB nanosheets exhibited unique enrichment selectivity toward monophosphopeptides. The 2-D MOF nanosheets demonstrated excellent sensitivity (detection limit of 0.4 fmol µL-1) and selectivity [1:1000 molar ratios of ß-casein/BSA (bovine serum albumin)] in model phosphopeptides enrichment. The nanosheets were implemented for the analysis of nonfat milk and human saliva samples as well as in situ isotope labeling for dysregulated phosphopeptides from patients' serum with anal canal inflammation, exhibiting 6.6-fold upregulation of serum phosphopeptide HS4 (ADpSGEGDFLAEGGGVR) compared to the control healthy serum. The proteomics analysis of mouse brain cortical samples associated with Alzheimer's disease, which were from Akt (protein kinase B) conditional knockout mouse and littermate control mouse, was further established with 2-D Hf-BTB nanosheets. With high capture efficiency for monophosphopeptides, this method was capable of distinguishing the difference of monophosphopeptides from microtubule-associated protein τ (MAPT/τ) between the Akt knockout sample and control sample.
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Estruturas Metalorgânicas/química , Nanoestruturas/química , Fosfopeptídeos/isolamento & purificação , Adulto , Doença de Alzheimer/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Inflamação/sangue , Limite de Detecção , Camundongos Knockout , Leite/química , Fosfopeptídeos/sangue , Proctite/sangue , Proteômica/métodos , Proteínas Proto-Oncogênicas c-akt/genética , Saliva/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Cucumber green mottle mosaic virus (CGMMV) is a single-stranded, positive sense RNA virus infecting cucurbitaceous plants. In recent years, CGMMV has become an important pathogen of cucurbitaceous crops including watermelon, pumpkin, cucumber and bottle gourd in China, causing serious losses to their production. In this study, we surveyed CGMMV infection in various cucurbitaceous crops grown in Zhejiang Province and in several seed lots purchased from local stores with the dot enzyme-linked immunosorbent assay (dot-ELISA), using a CGMMV specific monoclonal antibody. Seven CGMMV isolates obtained from watermelon, grafted watermelon or oriental melon samples were cloned and sequenced. Identity analysis showed that the nucleotide identities of the seven complete genome sequences ranged from 99.2 to 100%. Phylogenetic analysis of seven CGMMV isolates as well as 24 other CGMMV isolates from the GenBank database showed that all CGMMV isolates could be grouped into two distinct monophyletic clades according to geographic distribution, i.e. Asian isolates for subtype I and European isolates for subtype II, indicating that population diversification of CGMMV isolates may be affected by geographical distribution. Site variation rate analysis of CGMMV found that the overall variation rate was below 8% and mainly ranged from 2 to 5%, indicating that the CGMMV genomic sequence was conservative. Base substitution type analysis of CGMMV showed a mutational bias, with more transitions (AâG and CâT) than transversions (AâC, AâT, GâC and GâT). Most of the variation occurring in the CGMMV genome resulted in non-synonymous substitutions, and the variation rate of some sites was higher than 30% because of this mutational bias. Selection constraint analysis of CGMMV ORFs showed strong negative selection acting on the replication-associated protein, similar to what occurs for other plant RNA viruses. Finally, potential recombination analysis identified isolate Ec as a recombinant with a low degree of confidence.
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Citrullus/virologia , Cucumis sativus/virologia , Cucurbita/virologia , Variação Genética/genética , Genoma Viral/genética , Momordica/virologia , Tobamovirus/genética , Sequência de Bases , Doenças das Plantas/virologia , RNA Viral/genética , Análise de Sequência de DNA , Tobamovirus/isolamento & purificaçãoRESUMO
OBJECTIVE: Tranexamic acid (TXA) demonstrates therapeutic efficacy in the management of traumatic brain injury (TBI). The objective of this systematic review and meta-analysis was to evaluate the safety and effectiveness of TXA in patients with TBI. METHODS: The databases, namely PubMed, Embase, Web of Science, and Cochrane Library databases, were systematically searched to retrieve randomized controlled trials (RCTs) investigating the efficacy of TXA for TBI from January 2000 to November 2023. RESULTS: The present meta-analysis incorporates ten RCTs. Compared to the placebo group, administration of TXA in patients with TBI resulted in a significant reduction in mortality (P = 0.05), hemorrhage growth (P = 0.03), and volume of hemorrhage growth (P = 0.003). However, no significant impact was observed on neurosurgery outcomes (P = 0.25), seizure occurrence (P = 0.78), or pulmonary embolism incidence (P = 0.52). CONCLUSION: The administration of TXA is significantly associated with reduced mortality and hemorrhage growth in patients suffering from TBI, while the need of neurosurgery, seizures, and incidence of pulmonary embolism remains comparable to that observed with placebo.
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Antifibrinolíticos , Lesões Encefálicas Traumáticas , Embolia Pulmonar , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/uso terapêutico , Antifibrinolíticos/uso terapêutico , Hemorragia/tratamento farmacológico , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/complicações , Embolia Pulmonar/complicações , Embolia Pulmonar/tratamento farmacológicoRESUMO
Plant survival requires an ability to adapt to differing concentrations of nutrient and toxic soil ions, yet ion sensors and associated signaling pathways are mostly unknown. Aluminum (Al) ions are highly phytotoxic, and cause severe crop yield loss and forest decline on acidic soils which represent â¼30% of land areas worldwide. Here we found an Arabidopsis mutant hypersensitive to Al. The gene encoding a leucine-rich-repeat receptor-like kinase, was named Al Resistance1 (ALR1). Al ions binding to ALR1 cytoplasmic domain recruits BAK1 co-receptor kinase and promotes ALR1-dependent phosphorylation of the NADPH oxidase RbohD, thereby enhancing reactive oxygen species (ROS) generation. ROS in turn oxidatively modify the RAE1 F-box protein to inhibit RAE1-dependent proteolysis of the central regulator STOP1, thus activating organic acid anion secretion to detoxify Al. These findings establish ALR1 as an Al ion receptor that confers resistance through an integrated Al-triggered signaling pathway, providing novel insights into ion-sensing mechanisms in living organisms, and enabling future molecular breeding of acid-soil-tolerant crops and trees, with huge potential for enhancing both global food security and forest restoration.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Alumínio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Íons , Solo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/metabolismoRESUMO
Aim: The aim of the study was to compare the short-term surgical outcomes of robotic right colectomy (RRC) with laparoscopic right colectomy (LRC) for colon cancer, to evaluate the safety and feasibility of the robotic surgery system. Material and methods: A systematic literature review was conducted using the PubMed, Web of Science, Embase, and Cochrane Library databases regarding the comparison of RRC vs. LRC for colon cancer in the last 5 years. Studies were included as per the PICOS criteria, and relevant event data were extracted. Results: Fifteen studies (RRC: 1116 patients; LRC: 4036 patients) were evaluated. RRC demonstrated lower conversion to laparotomy (p = 0.03) and shorter length of hospital stay (p = 0.01), compared with LRC. However, operation times were longer in RRC than in LRC (p < 0.001). The estimated blood loss, retrieved lymph nodes, and overall postoperative complications were similar between RRC and LRC (p > 0.05). Conclusions: RRC can be regarded as a feasible and safe technique for colon cancer.
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Acute respiratory failure and sudden cardiac arrest caused by acute intrathoracic infection is a fatal clinical condition with a low resuscitation success rate. The present study describes the case of a patient with acute empyema secondary to an acute lung abscess rupture, complicated by acute respiratory failure and sudden cardiac arrest caused by severe hypoxemia. The patient recovered well through the administration of multiple therapeutic measures, including medication and closed chest drainage, cardiopulmonary resuscitation, extracorporeal membrane oxygenation combined with continuous renal replacement therapy, and minimally invasive surgical resection of the lung lesion with persistent alveolar fistula as the clinical manifestation. To the best of our knowledge, the treatment of such a severe condition combined with thoracoscopic surgery has rarely been reported before, and the present study may provide insight regarding therapeutic schedules for acute respiratory failure by intrathoracic infection, and excision of ruptured lung abscess.
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Macroautophagy/autophagy is an important innate and adaptive immune response that can clear microbial pathogens through guiding their degradation. Virus infection in animals and plants is also known to induce autophagy. However, how virus infection induces autophagy is largely unknown. Here, we provide evidence that the early phase of rice black-streaked dwarf virus (RBSDV) infection in Laodelphax striatellus can also induce autophagy, leading to suppression of RBSDV invasion and accumulation. We have determined that the main capsid protein of RBSDV (P10) is the inducer of autophagy. RBSDV P10 can specifically interact with GAPDH (glyceraldehyde-3-phosphate dehydrogenase), both in vitro and in vivo. Silencing of GAPDH in L. striatellus could significantly reduce the activity of autophagy induced by RBSDV infection. Furthermore, our results also showed that both RBSDV infection and RBSDV P10 alone can promote phosphorylation of AMP-activated protein kinase (AMPK), resulting in GAPDH phosphorylation and relocation of GAPDH from the cytoplasm into the nucleus in midgut cells of L. striatellus or Sf9 insect cells. Once inside the nucleus, phosphorylated GAPDH can activate autophagy to suppress virus infection. Together, these data illuminate the mechanism by which RBSDV induces autophagy in L. striatellus, and indicate that the autophagy pathway in an insect vector participates in the anti-RBSDV innate immune response.Abbreviations3-MA: 3-methyladenine; AMPK: AMP-activated protein kinase; ATG: autophagy-related; co-IP: co-immunoprecipitation; DAPI: 4',6-diamidino-2-phenylindole; dpf: days post-feeding; dsRNA: double-stranded RNA; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GST: glutathione-S-transferase; RBSDV: Rice black-streaked dwarf virus; TEM: transmission electron microscope.
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Proteínas Quinases Ativadas por AMP , Hemípteros , Animais , Autofagia , Gliceraldeído-3-Fosfato Desidrogenases , Fosforilação , Vírus de PlantasRESUMO
Zirconium (Zr)-based porphyrinic metal-organic frameworks (PCN-223-M) were employed as the electrocatalysts to explore the effect of uncoordinated Zr sites on the performance of the CO2 reduction reaction (CO2RR). PCN-223-AA with the lowest uncoordinated number of 0.79 exhibited the highest FE(CO) of 90.7%. It was demonstrated that the catalytic performance of PCN-223-M showed negative correlation to the uncoordinated Zr sites. This research provided a rational strategy to design efficient MOF electrocatalysts with few uncoordinated metal sites for highly selective CO2RR.
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PURPOSE: To compare the specificity and sensitivity of preoperative D-dimer and age-adjusted D-dimer value for predicting the incidence of the DVT preoperatively in total joint arthroplasty (TJA) patients. METHODS: We enrolled 406 patients finally above 50 years old. Everyone had done ultrasonography bedside, and D-dimer concentrations were collected before surgery. The D-dimer and age-adjusted D-dimer cut-off was calculated by multiple logistic regression and receiver operating curve (ROC) analyses. RESULTS: A total of 39 patients had found asymptomatic deep vein thrombosis (DVT) by ultrasonography. The age (odds ratio [OR] 1.067; p = 0.003) and D-dimer (OR 1.331; p = 0.025) were related to the existence of DVT. For conventional D-dimer and age-adjusted D-dimer value, the area under the curves (AUCs) were 0.685 (0.499-0.696) and 0.795 (0.611-0.881), respectively. CONCLUSION: Compared to traditional D-dimer, age-adjusted D-dimer showed better performance in screening DVT, which was useful clinically.
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Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Complicações Pós-Operatórias/diagnóstico , Trombose Venosa/diagnóstico , Idoso , Biomarcadores/sangue , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Período Pré-Operatório , Curva ROC , Sensibilidade e Especificidade , Trombose Venosa/etiologiaRESUMO
Sn-based metal-organic framework (MOF) was utilized to effectively capture monophosphopeptides due to the unique affinity. The Sn-based MOF demonstrated the good sensitivity and selectivity in the model phosphoproteins enrichment and was successfully applied in the biological fluids.
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Estruturas Metalorgânicas , FosfoproteínasRESUMO
Pepino mosaic virus (PepMV) causes severe disease in tomato and other Solanaceous crops around globe. To effectively study and manage this viral disease, researchers need new, sensitive, and high-throughput approaches for viral detection. In this study, we purified PepMV particles from the infected Nicotiana benthamiana plants and used virions to immunize BALB/c mice to prepare hybridomas secreting anti-PepMV monoclonal antibodies (mAbs). A panel of highly specific and sensitive murine mAbs (15B2, 8H6, 23D11, 20D9, 3A6, and 8E3) could be produced through cell fusion, antibody selection, and cell cloning. Using the mAbs as the detection antibodies, we established double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), Dot-ELISA, and Tissue print-ELISA for detecting PepMV infection in tomato plants. Resulting data on sensitivity analysis assays showed that both DAS-ELISA and Dot-ELISA can efficiently monitor the virus in PepMV-infected tissue crude extracts when diluted at 1:1 310 720 and 1:20 480 (weight/volume ratio (w/v), g/mL), respectively. Among the three methods developed, the Tissue print-ELISA was found to be the most practical detection technique. Survey results from field samples by the established serological approaches were verified by reverse transcription polymerase chain reaction (RT-PCR) and DNA sequencing, demonstrating all three serological methods are reliable and effective for monitoring PepMV. Anti-PepMV mAbs and the newly developed DAS-ELISA, Dot-ELISA, and Tissue print-ELISA can benefit PepMV detection and field epidemiological study, and management of this viral disease, which is already widespread in tomato plants in Yunnan Province of China.
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Potexvirus/metabolismo , Solanum lycopersicum/virologia , Animais , Anticorpos Monoclonais/imunologia , China , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hibridomas , Camundongos , Camundongos Endogâmicos BALB C , Doenças das Plantas/virologia , Sensibilidade e Especificidade , NicotianaRESUMO
Brassinosteroids (BRs) are a new group of plant growth substances that promote plant growth and productivity. We showed in this study that improved growth of cucumber (Cucumis sativus) plants after treatment with 24-epibrassinolide (EBR), an active BR, was associated with increased CO(2) assimilation and quantum yield of PSII (Phi(PSII)). Treatment of brassinazole (Brz), a specific inhibitor for BR biosynthesis, reduced plant growth and at the same time decreased CO(2) assimilation and Phi(PSII). Thus, the growth-promoting activity of BRs can be, at least partly, attributed to enhanced plant photosynthesis. To understand how BRs enhance photosynthesis, we have analyzed the effects of EBR and Brz on a number of photosynthetic parameters and their affecting factors, including the contents and activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). Northern and Western blotting demonstrated that EBR upregulated, while Brz downregulated, the expressions of rbcL, rbcS and other photosynthetic genes. In addition, EBR had a positive effect on the activation of Rubisco based on increased maximum Rubisco carboxylation rates (V (c,max)), total Rubisco activity and, to a greater extent, initial Rubisco activity. The accumulation patterns of Rubisco activase (RCA) based on immunogold-labeling experiments suggested a role of RCA in BR-regulated activation state of Rubisco. Enhanced expression of genes encoding other Calvin cycle genes after EBR treatment may also play a positive role in RuBP regeneration (J (max)), thereby increasing maximum carboxylation rate of Rubisco (V (c,max)). Thus, BRs promote photosynthesis and growth by positively regulating synthesis and activation of a variety of photosynthetic enzymes including Rubisco in cucumber.
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Colestanóis/farmacologia , Cucumis sativus/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Esteroides Heterocíclicos/farmacologia , Biomassa , Western Blotting , Brassinosteroides , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Colestanóis/metabolismo , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Hexoses/metabolismo , Cinética , Fotossíntese/genética , Fotossíntese/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribulose-Bifosfato Carboxilase/genética , Amido/metabolismo , Esteroides Heterocíclicos/metabolismo , Sacarose/metabolismo , Triazóis/farmacologiaRESUMO
OBJECTIVE: To investigate the effects of Shexiang Baoxin Pill (SBP) on function of endothelial progenitor cells (EPCs) and its nitric oxide (NO) secretion. METHODS: Total mononuclear cells were isolated from human peripheral blood by ficoll density gradient centrifugation and inoculated on the human fibro-ligandin encrusting plate. After 7 days of in vitro culture, adherent cells were collected and incubated with SBP for 24 h. The proliferation, migration, adhesive activity, vasculogenesis capacity and NO secretion of EPCs were assayed using MTT, Transwell chamber, adhesion determination, in vitro vasculogenesis kit and nitrate reductase method, respectively. RESULTS: EPCs incubated with SBP showed the capacities higher than those of control in proliferation, migration, adhesion, in vitro vasculogenesis, and with a higher NO concentration in the culture supernatant. CONCLUSION: SBP can improve the function of EPCs, which might be a novel mechanism of its effects in improving vascular endothelial function and promoting angiogenesis.
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Diferenciação Celular/fisiologia , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/metabolismo , Óxido Nítrico/biossíntese , Células-Tronco/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Humanos , Leucócitos Mononucleares/citologia , Células-Tronco/citologia , Células-Tronco/fisiologiaRESUMO
Ultrathin 2D nickel(II) (Ni2+) and imidazole (Im) based zeolitic imidazolate framework Ni(Im)2 nanosheets are reported as exceptional efficient electrocatalysts for the electrocatalytic CO2 reduction reaction. Five nanometre thick nanosheets have a higher faradaic efficiency of 78.8% and a surface active site density of 1.68 × 10-7 mol cm-2, which is superior to those of thicker nanosheets and bulk Ni(Im)2.
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An efficient and selective Cu catalyst for CO2 electroreduction is highly desirable since current catalysts suffer from poor selectivity towards a series of products, such as alkenes, alcohols, and carboxylic acids. Here, we used copper(ii) paddle wheel cluster-based porphyrinic metal-organic framework (MOF) nanosheets for electrocatalytic CO2 reduction and compared them with CuO, Cu2O, Cu, a porphyrin-Cu(ii) complex and a CuO/complex composite. Among them, the cathodized Cu-MOF nanosheets exhibit significant activity for formate production with a faradaic efficiency (FE) of 68.4% at a potential of -1.55 V versus Ag/Ag+. Moreover, the C-C coupling product acetate is generated from the same catalyst together with formate at a wide voltage range of -1.40 V to -1.65 V with the total liquid product FE from 38.8% to 85.2%. High selectivity and activity are closely related to the cathodized restructuring of Cu-MOF nanosheets. With the combination of X-ray diffraction, X-ray photoelectron spectroscopy, high resolution transmission electron microscopy and Fourier transform infrared spectroscopy, we find that Cu(ii) carboxylate nodes possibly change to CuO, Cu2O and Cu4O3, which significantly catalyze CO2 to formate and acetate with synergistic enhancement from the porphyrin-Cu(ii) complex. This intriguing phenomenon provides a new opportunity for the rational design of high-performance Cu catalysts from pre-designed MOFs.
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Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20 480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/µL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.
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Cromatografia de Afinidade/métodos , Doenças das Plantas/virologia , Tenuivirus/isolamento & purificação , Anticorpos Monoclonais/química , China , Colódio/química , Coloides/química , Coloide de Ouro/química , Teste de Materiais , Membranas Artificiais , Oryza/virologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da EspécieRESUMO
The stacking between nanosheets is an intriguing and inevitable phenomenon in the chemistry of nano-interfaces. Two-dimensional metal-organic framework nanosheets are an emerging type of nanosheets with ultrathin and porous features, which have high potential in separation applications. Here, the stacking between single-layer metal-organic framework nanosheets is revealed to show three representative conformations with tilted angles of 8°, 14°, and 30° for Zr-1, 3, 5-(4-carboxylphenyl)-benzene framework as an example. Efficient untwisted stacking strategy by simple heating is proposed. A detailed structural analysis of stacking modes reveals the creation of highly ordered sub-nanometer micropores in the interspacing of untwisted nano-layers, yielding a high-resolution separator for the pair of para-/meta-isomers over the twisted counterparts and commercial HP-5MS and VF-WAXMS columns. This general method is proven by additional nanosheet examples and supported by Grand Canonical Monte Carlo simulation. This finding will provide a synthetic route in the rational design of functionalities in two-dimensional metal-organic framework nanosheet.