RESUMO
Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that CâC bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.
RESUMO
Carbon-carbon coupling electrochemistry on a conventional copper (Cu) catalyst still undergoes low selectivity among many different multicarbon (C2+) chemicals, posing a grand challenge to achieve a single C2+ product. Here, we demonstrate a laser irradiation synthesis of a gerhardtite mineral, Cu2(OH)3NO3, as a catalyst precursor to make a Cu catalyst with abundant stacking faults under reducing conditions. Such structural perturbation modulates electronic microenvironments of Cu, leading to improved d-electron back-donation to the antibonding orbital of *CO intermediates and thus strengthening *CO adsorption. With increased *CO coverage on the defect-rich Cu, we report an acetate selectivity of 56 ± 2% (compared to 31 ± 1% for conventional Cu) and a partial current density of 222 ± 7 mA per square centimeter in CO electroreduction. When run at 400 mA per square centimeter for 40 h in a flow reactor, this catalyst produces 68.3 mmol of acetate throughout. This work highlights the value of a Cu-containing mineral phase in accessing suitable structures for improved selectivity to a single desired C2+ product.
RESUMO
BACKGROUND: Branchio-oto-renal (BOR) syndrome is a dominant autosomal disorder characterized by phenotypes such as hearing loss, branchial fistulae, preauricular pits, and renal abnormalities. EYA1, the human homolog of the Drosophila "eye absent" gene on chromosome 8q13.3, is recognized as one of the most important genes associated with BOR syndrome. METHODS: The proposita in this study was a 5-year-old Chinese girl with hearing loss, bilateral otitis media with effusion, microtia, facial hypoplasia, palatoschisis, and bilateral branchial cleft fistulae. The girl's family members, except two who were deceased, agreed to undergo clinical examination. We collected blood samples from 10 family members, including six who were affected by the syndrome. Genomic DNA was extracted and subjected to Sanger sequencing. A minigene assay was performed to confirm whether splicing signals were altered. In addition, we performed western blotting to determine alterations in protein levels of the wild-type and mutant gene. RESULTS: Clinical tests showed that some of the family members met the criteria for BOR syndrome. The affected members harbored a novel heterozygous nonsense variation in exon 11 of EYA1, whereas no unaffected member carried the mutation at this position. Functional experiments did not detect abnormal splicing at the RNA level; however, western blotting showed that the mutated protein was truncated. CONCLUSIONS: This study reports a novel mutation associated with BOR syndrome in a Chinese family. We highlight the usefulness of genetic testing in the diagnosis of BOR syndrome. Thus, we believe that this report would benefit clinicians in this field.
Assuntos
Síndrome Brânquio-Otorrenal/genética , Códon sem Sentido/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética , Povo Asiático , Pré-Escolar , DNA/genética , Éxons/genética , Feminino , Perda Auditiva/genética , Humanos , Masculino , Otite Média/genética , Linhagem , FenótipoRESUMO
Combivena Sheng & Sun, gen.n. and Combivena sulcata Sheng & Sun, sp.n. belonging to Acaenitinae of family Ichneumonidae (Hymenoptera), collected from Qinghai Province, China, are described and illustrated.
Assuntos
Vespas/classificação , Animais , China , Vespas/anatomia & histologiaRESUMO
Three new species of Mesoleptidea Viereck, 1912: M. nigra Li & Sun, sp. nov., M. nigricoxalis Li & Sun, sp. nov. and M. ruficoxalis Li & Sun, sp. nov., collected from the National Forest Park of Mt Wawu and Mt Laojun, Sichuan, on the southern border of the Eastern Palaearctic part of China, are described. A key to species of Mesoleptidea known in China and Eastern Palaearctic region is provided.
Assuntos
Himenópteros , Animais , ChinaRESUMO
Seven species of Xenoschesis Förster, 1869, are reported from China. Four species, X. (Polycinetis) inareolata Sheng & Sun, sp. n. from Liaoning Province, X. (Polycinetis) truncata Sheng & Sun, sp. n. from Liaoning, Jilin and Henan Provinces, X. (Xenoschesis) tianzhuensis Sheng & Sun, sp. n. and X. (Xenoschesis) weii Sheng & Sun, sp. n. collected in Anhui Province are new to science. One, X. (Xenoschesis) fulvipes (Gravenhorst) was reared from Acantholyda parki Shinohara & Byun and A. posticalis Matsumura, is new record for China. Xenoschesis (Xenoschesis) crassicornis Uchida was reared from A. erythrocephala (L.) and A. parki Shinohara & Byun. A key to species of Xenoschesis Förster known in China is provided.
Assuntos
Psychodidae/parasitologia , Vespas/classificação , Vespas/parasitologia , Animais , China , Feminino , Masculino , Pupa/anatomia & histologia , Pupa/parasitologia , Pupa/fisiologia , Especificidade da Espécie , Vespas/anatomia & histologia , Vespas/fisiologiaRESUMO
Larvae of the argid sawfly, Arge pullata (Zaddach) (Hymenoptera: Argidae), feeds on leaves of birch (Betula spp.) in China, Europe, Siberia, and Japan. Parasitoids of A. pullata were studied in Shennongjia National Nature Reserve, Hubei Province, China, in 2009 and 2010. Five parasitoid species were found: Pleolophus suigensis (Uchida), Mastrus nigrus Sheng, Endasys parviventris nipponicus (Uchida) (Hymenoptera: Ichneumonidae), Vibrissina turrita (Meigen) (Diptera: Tachinidae) and Conura xanthostigma (Dalman) (Hymenoptera: Chalcididae). The average parasitism rate of A. pullata by parasitoids was as high as 11.0%. V. turrita was the dominant species, attacking 10.0% of the A. pullata cocoons. The emergence peak of V. turrita was from late May to early June. Three hyperparasitoids of V. turrita emerged from cocoons of A. pullata: Mesochorus ichneutese Uchida (Hymenoptera: Ichneumonidae), Pediobius sp. (Hymenoptera: Eulophidae), and Taeniogonalos maga (Teranishi) (Hymenoptera: Trigonalidae). Hyperparasitism rates were about 1.0% to 3.0%, with an average rate of 1.7%.
Assuntos
Dípteros/fisiologia , Himenópteros/fisiologia , Himenópteros/parasitologia , Animais , Agentes de Controle Biológico , China , Dípteros/crescimento & desenvolvimento , Interações Hospedeiro-Parasita , Himenópteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/parasitologia , Pupa/fisiologiaRESUMO
Laxiareola Sheng and Sun, gen.nov. and Laxiareola ochracea Sheng and Sun, sp.nov. belong to Brachyscleromatinae of the family Ichneumonidae, from the Jiangxi Province in China, are described in the present study. A key to the genera of Brachyscleromatinae is given.
Assuntos
Vespas/classificação , Animais , China , Feminino , Vespas/anatomia & histologiaRESUMO
Two new species of Alcochera (Ichneumonidae, Ctenopelmatinae, Mesoleiini), Alcochera flavoclypeata Sheng Sun, sp. nov. collected from Labagoumen Natural Reserve, Huairou, Beijing, and A. truncata Sheng Sun, sp. nov. from Wugongshan Natural Reserve, are described and illustrated. An updated taxonomic key to world species of Alcochera is provided.
Assuntos
Himenópteros , Animais , ChinaRESUMO
The genus Microstenus Szépligeti, 1916 (Hymenoptera: Ichneumonidae: Cryptinae) is newly recorded from China based on a new species, Microstenus rufithorax Sheng, Li Sun, sp. nov., collected from Guangxi Zhuang Autonomous Region, Oriental part of China. Illustrations of the new species are provided. A key to the world species of this genus is also provided.
Assuntos
Himenópteros , Animais , ChinaRESUMO
Five species of the genus Townesia Ozols are reported. One, Townesia sulcata Sheng & Li, sp. nov. collected from Liaoning province, China, is new to science. In addition, digital images and a taxonomic key to the all species of Townesia are presented.
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A new species, Alexeterbeijingensis Sheng, sp. nov., and two new records for China, A.angularis (Uchida, 1952) and A.shakojiensis Uchida, 1930, collected in Mentougou, Beijing, belonging to the tribe Mesoleiini of the subfamily Ctenopelmatinae (Hymenoptera, Ichneumonidae), are reported. A key to the six species of Alexeter known from China is given.
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A new genus, Verruca Sheng Sun gen. nov., of the ichneumonid tribe Atrophini, subfamily Banchinae is described for one new species, Verruca dentia Sheng Sun, sp. nov. The species was collected from Shandong and Jiangxi Provinces, situated near the northern border of the Oriental part of China. The new genus is placed within the existing key to genera. A key to the genera of Atrophini, with the apical portion of the ovipositor with ridges, is also provided.
Assuntos
Himenópteros , Animais , China , ThoracicaRESUMO
A new species of Poemeniinae, Poemenia quercusia Sun & Sheng, sp. n., is described and illustrated. Specimens were reared from twigs of Quercus wutaishanica Blume in Haicheng, Liaoning province, P.R. China. A key to species known from China and the Eastern Palaearctic Region is provided.
RESUMO
A new species of Eulophinae, Pnigalio eriocraniae Li & Yang, sp. n., is described and illustrated. This new species is a larval ectoparasitoid of Eriocrania semipurpurella alpina Xu (Lepidoptera, Eriocraniidae), a leaf miner in birch trees, Betula spp. (Betulaceae), in Qinghai Province, northwest China. The biology of the new species and a key to the known species from China are provided.
RESUMO
In this study, we demonstrate that N-ethylmaleimide (NEM), a cell permeable thiol-alkylating agent, enhanced the [Ca2+]i rise caused by stimulation with cyclopiazonic acid (CPA), a sarcoplasmic-endoplasmic reticulum Ca2+-ATPase inhibitor, in rat neutrophils. In addition, NEM attenuated the formyl-Met-Leu-Phe (fMLP)-induced [Ca2+]i rise whether NEM was added to cells prior to or after fMLP stimulation. Moreover, application of NEM after fMLP activation in the absence of external Ca2+ inhibited the Ca2+ signal upon addition of Ca2+ to the medium. Similar patterns were also obtained by using 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), a cell impermeable dithiol-oxidizing agent, which replaced NEM in the CPA- and fMLP-induced [Ca2+]i rise experiments. Treatment with dithiothreitol (DTT), a cell permeable dithiol-reducing agent, N-acetyl-l-cysteine (NAC), a cell permeable monothiol-reducing agent, and tris-(2-carboxyethyl)phosphine (TCEP), a cell impermeable reductant without a thiol group, all rescued the fMLP-induced Ca2+ signal from NEM. Rat neutrophils express the mRNA encoding for transient receptor potential (TRP) C6, inositol trisphosphate receptor (IP3R) 2 and IP3R3. NEM had no effect on the mitochondrial membrane potential. NEM could restore the polarization and F-actin accumulation of fMLP-treated cells to those of the control. In the absence of external Ca2+, NEM rendered the CPA-induced [Ca2+]i elevation persistently but inhibited the fMLP-induced Ca2+ spike, which was reversed by tris-(2-cyanoethyl)phosphine (TCP), a cell permeable reductant without a thiol group. DTNB did not affect the Ca2+ spike caused by fMLP. These results indicate that through protein thiol oxidation, NEM affects the receptor-activated and the store depletion-derived Ca2+ signals in an opposing manner.
Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Etilmaleimida/farmacologia , Indóis/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/metabolismo , Compostos de Sulfidrila/metabolismo , Actinas/química , Animais , Canais de Cálcio/análise , Ácido Ditionitrobenzoico/farmacologia , Receptores de Inositol 1,4,5-Trifosfato , Masculino , Potenciais da Membrana/efeitos dos fármacos , Fosfinas/farmacologia , RNA Mensageiro/análise , Ratos , Receptores Citoplasmáticos e Nucleares/análise , Canais de Cátion TRPC/genéticaRESUMO
A new species, Notopygus longiventris Sun & Sheng, sp. n., collected from Benxi County, Liaoning Province, China, and N. emarginatus Holmgren, 1857, reared from Neurotoma sibirica Gussakovskij (Hymenoptera, Pamphiliidae) from Haicheng, Liaoning Province, are reported. The new species is placed within existing key to species.
RESUMO
A new species, Amphibulus melanarius Zong, Sun & Sheng, sp.n., belonging to the tribe Phygadeuontini of the subfamily Cryptinae (Hymenoptera: Ichneumonidae), collected from Beijing, China, is reported. A key to the species of the genus Amphibulus Kriechbaumer, 1893 known in the Oriental and Eastern Palaearctic Regions is provided.
RESUMO
Six species of the genus Aptesis Förster 1850 belonging to the tribe Hemigastrini of the subfamily Cryptinae (Hymenoptera, Ichneumonidae) are reported from China. Three of them, Aptesis elongata Li & Sheng, sp. n., Aptesis melana Li & Sheng, sp. n. and Aptesis nigricoxa Li & Sheng, sp. n. reared from sawflies in China, are new to science. The biology of Aptesis melana is described. A key to the species of Aptesis known from China is provided.
RESUMO
A new species, Syntactus jiulianicus Sun & Sheng, sp.n. belonging to the tribe Pionini of the subfamily Ctenopelmatinae (Hymenoptera, Ichneumonidae), collected from Jiangxi Province, China, is reported. Illustrations of the new species and Syntactus delusor (Linnaeus, 1758), Syntactus minor (Holmgren, 1857) and Syntactus varius (Holmgren, 1858) are provided. A key to the species of Syntactus known from the Oriental and Eastern Palaearctic Regions is given.