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Iron sulfide (FeS) is a promising material for separating copper and arsenic from strongly acidic wastewater due to its S2- slow-release effect. However, uncertainties arise because of the constant changes in wastewater composition, affecting the selection of operating parameters and FeS types. In this study, the aging method was first used to prepare various controllable FeS nanoparticles to weaken the arsenic removal ability without affecting the copper removal. Orthogonal experiments were conducted, and the results identified the Cu/As ratio, H2SO4 concentration, and FeS dosage as the three main factors influencing the separation efficiency. The backpropagation artificial neural network (BP-ANN) model was established to determine the relationship between the influencing factors and the separation efficiency. The correlation coefficient (R) of overall model was 0.9923 after optimizing using genetic algorithm (GA). The BP-GA model was also solved using GA under specific constraints, predicting the best solution for the separation process in real-time. The predicted results show that the high temperature and long aging time of FeS were necessary to gain high separation efficiency, and the maximum separation factor can reached 1,400. This study provides a suitable sulfurizing material and a set of methods and models with robust flexibility that can successfully predict the separation efficiency of copper and arsenic from highly acidic environments.
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Arsênio , Cobre , Águas Residuárias , Inteligência ArtificialRESUMO
INTRODUCTION: Headache during and/or after coronary intervention is common but has received little attention from cardiologists and neurologists. The purpose of this study was to investigate the incidence, risk factors, and possible mechanism of coronary intervention-related headache. METHODS: Using a prospective observational design, we identified consecutive patients with coronary intervention from May 2020 to August 2020. Patients were followed up with questionnaires immediately after coronary intervention and 24 h, 72 h, 1 week and 2 weeks after the intervention. RESULTS: In total, 94 patients were enrolled, and 71 patients ultimately completed the 2-week follow-up. Among 71 patients, headache developed during and/or after coronary intervention in 18 (25.4%) patients. Two different types of headache related to coronary intervention were observed: One during and another after coronary intervention. Headache characteristics are described in detail. A history of previous headache was an independent risk factor for coronary intervention-related headache (p < 0.01). CONCLUSIONS: Coronary intervention-related headache has an incidence of 25.4%, and previous headache history was an independent risk factor. Moreover, considering that there are no relevant diagnostic criteria, it is suggested that the definition of coronary intervention-related headache should be established in the International Classification of Headache Disorders.
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Transtornos da Cefaleia , Cefaleia , Cefaleia/diagnóstico , Cefaleia/epidemiologia , Cefaleia/etiologia , Transtornos da Cefaleia/diagnóstico , Humanos , Incidência , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Astrocytic activation might play a significant role in the central sensitization of chronic migraine (CM). However, the temporal characteristics of the astrocytic activation in the trigeminal nucleus caudalis (TNC) and the molecular mechanism under the process remain not fully understood. Therefore, this study aims to investigate the duration and levels change of astrocytic activation and to explore the correlation between astrocytic activation and the levels change of cytokines release. METHODS: We used a mice model induced by recurrent dural infusion of inflammatory soup (IS). The variation with time of IS-induced mechanical thresholds in the periorbital and hind paw plantar regions were evaluated using the von Frey filaments test. We detected the expression profile of glial fibrillary acidic protein (GFAP) in the TNC through immunofluorescence staining and western blot assay. We also investigated the variation with time of the transcriptional levels of GFAP and ionized calcium binding adapter molecule 1 (Iba1) through RNAscope in situ hybridization analysis. Then, we detected the variation with time of cytokines levels in the TNC tissue extraction and serum, including c-c motif chemokine ligand 2 (CCL2), c-c motif chemokine ligand 5 (CCL5), c-c motif chemokine ligand 7 (CCL7), c-c motif chemokine ligand 12 (CCL12), c-x-c motif chemokine ligand 1 (CXCL1), c-x-c motif chemokine ligand 13 (CXCL13), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), macrophage colony-stimulating factor (M-CSF), interleukin 1beta (IL-1ß), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 17A (IL-17A). RESULTS: Recurrent IS infusion resulted in cutaneous allodynia in both the periorbital region and hind paw plantar, ranging from 5 d (after the second IS infusion) to 47 d (28 d after the last infusion) and 5 d to 26 d (7 d after the last infusion), respectively. The protein levels of GFAP and messenger ribonucleic acid (mRNA) levels of GFAP and Iba1 significantly increased and sustained from 20 d to 47 d (1 d to 28 d after the last infusion), which was associated with the temporal characteristics of astrocytic activation in the TNC. The CCL7 levels in the TNC decreased from 20 d to 47 d. But the CCL7 levels in serum only decreased on 20 d (1 d after the last infusion). The CCL12 levels in the TNC decreased on 22 d (3 d after the last infusion) and 33 d (14 d after the last infusion). In serum, the CCL12 levels only decreased on 22 d. The IL-10 levels in the TNC increased on 20 d. CONCLUSIONS: Our results indicate that the astrocytic activation generated and sustained in the IS-induced mice model from 1 d to 28 d after the last infusion and may contribute to the pathology through modulating CCL7, CCL12, and IL-10 release.
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Transtornos de Enxaqueca , Núcleos do Trigêmeo , Animais , Sensibilização do Sistema Nervoso Central , Hiperalgesia/induzido quimicamente , Camundongos , DorRESUMO
BACKGROUND: Angiography headache (AH) is common but not negligible, and the criteria for AH have been based on only a few studies. The purpose of this study was to investigate the incidence, risk factors and possible mechanism of AH and reappraise the diagnostic criteria for AH in the International Classification of Headache Disorders 3 (ICHD-3). METHODS: Two hundred and seventy-nine patients completed this prospective, non-randomized study, including 107 patients who underwent cerebral angiography, 101 patients who underwent coronary intervention and 71 patients who underwent extremities arterial intervention. Patients were followed up with questionnaires immediately after the procedure and 24 h, 72 h, 1 week and 2 weeks after the procedure. RESULTS: The incidence of headache was 22.4% (24/107) in cerebral angiography group, 23.8% (24/101) in coronary intervention group, and 16.9% (12/71) in extremities arterial intervention group. Headache still occurred in 12.1% (13/107), 14.9% (15/101) and 11.3% (8/71) of patients 24 h after the procedure in the three groups, respectively. Two types of headache were observed in cerebral angiography group and coronary intervention group, one during and one after the procedure, while only postoperative headache was observed in extremities arterial intervention group. Previous headache history was a risk factor for headache in the three groups (p = 0.003 in cerebral angiography group, p = 0.006 in coronary intervention group, and p = 0.016 in extremities arterial intervention group). In addition, female (p = 0.008) was a risk factor for cerebral angiography group. Headache characteristics were described in detail. CONCLUSIONS: The diagnostic criteria for 6.7.2 angiography headache in ICHD-3 may miss a number of cerebral AH with onset later than 24 h after the procedure. Therefore, it is recommended to revise it according to the literature and further studies. The incidence of headache was high during and after angiography and interventional procedure. It was suggested that the definition of headache due to coronary intervention and headache due to extremities arterial intervention should be added in ICHD.
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Transtornos da Cefaleia , Angiografia Cerebral , Feminino , Cefaleia/diagnóstico , Cefaleia/epidemiologia , Humanos , Classificação Internacional de Doenças , Estudos ProspectivosRESUMO
Discovering the underlying reason for Li anode failure is a critical step towards applications of lithium metal batteries (LMBs). In this work, we conduct deuterium-oxide (D2 O) titration experiments in a novel on-line gas analysis mass spectrometry (MS) system, to determine the content of metallic Li and lithium hydride (LiH) in cycled Li anodes disassembled from practical LiCoO2 /Li LMBs. The practical cell is comprised of ultrathin Li anode (50â µm), high loading LiCoO2 (17â mg cm-2 , 2.805â mAh cm-2 ) and different formulated electrolytes. Our results suggest that the amount of LiH accumulation is negatively correlated with cyclability of practical LMBs. More importantly, we reveal a temperature sensitive equilibrium (Li + 1/2 H2 â LiH) governing formation and decomposition process of LiH at Li anode. We believe that the unusual understanding provided by this study will draw forth more insightful efforts to realize efficient Li protection and the ultimate applications of "holy grail" LMBs.
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Magnesium (Mg) metal anode is a highly desirable candidate among various high energy density metal anodes, possessing higher volumetric capacity and better safety characteristic compared to lithium metal. However, most Mg salts in conventional Mg electrolytes easily react with Mg metal to form blocking layers, leading to inferior reversibility of Mg plating/stripping. Here, a stable Mg2+ -conducting solid electrolyte interphase (SEI) is successfully constructed on Mg metal anode by regulating the molecular-orbital-energy-level toward an aluminum(III)-centered anion Mg salt through anion-solvent coordination. Of which, the LUMO energy level of perfluorinated pinacolatoaluminate (Al(O2 C2 (CF3 )4 )2 - , abbreviated as FPA) anion has been adjusted by coordinating with solvent molecule (tetrahydrofuran) for facilitating the formation of advantageous SEI. The existence of SEI formed by FPA anion greatly improves the reversibility and long-term stability of Mg plating/stripping process. More importantly, based on this aluminum(III)-centered Mg electrolyte, the Mo6 S8 /Mg batteries can achieve a fantastic cycle performance of 9000 cycles, proving the beneficial effect of SEI on the cycling stability of Mg battery system. These findings open up a promising avenue to construct stable and compatible SEI on Mg metal anode, and lay significant foundations for the successful development of rechargeable Mg metal batteries.
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Lithium (Li) metal batteries (LMBs) are enjoying a renaissance due to the high energy densities. However, they still suffer from the problem of uncontrollable Li dendrite and pulverization caused by continuous cracking of solid electrolyte interphase (SEI) layers. To address these issues, developing spontaneously built robust polymer-reinforced SEI layers during electrochemical conditioning can be a simple yet effective solution. Herein, a robust homopolymer of cyclic carbonate urethane methacrylate is presented as the polymer matrix through an in situ polymerization method, in which cyclic carbonate units can participate in building a stable polymer-integrated SEI layer during cycling. The as-investigated gel polymer electrolyte (GPE) assembled LiCoO2 /Li metal batteries exhibit a fantastic cyclability with a capacity retention of 92% after 200 cycles at 0.5 C (1 C = 180 mAh g-1 ), evidently exceeding that of the counterpart using liquid electrolytes. It is noted that the anionic ring-opening polymerization of the cyclic carbonate units on the polymer close to the Li metal anodes enables a mechanically reinforced SEI layer, thus rendering excellent compatibility with Li anodes. The in situ formed polymer-reinforced SEI layers afford a splendid strategy for developing high voltage resistant GPEs compatible with Li metal anodes toward high energy LMBs.
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Lymphomatoid granulomatosis (LYG) is an angiocentric and angiodestructive lymphoproliferative disease which can involve multiple organs of the body and is most common in the lungs. Its pathological features are proliferation of large atypical B-cells related to Epstein-Barr virus, T-cell infiltration and tissue necrosis. This disease is rare, and LYG which uniquely involves the central nervous system (CNS) is extremely rare. In this paper, we report a case of isolated lymphomatoid granulomatosis of the CNS (iCNS-LYG) diagnosed by histological biopsy and we review the clinical features of all similar cases reported in the past 46 years. A total of 49 cases of iCNS-LYG have been reported to date. The clinical, imaging and pathological features of iCNS-LYG are discussed in combination with a literature review.
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Neoplasias Encefálicas/diagnóstico por imagem , Granulomatose Linfomatoide/diagnóstico por imagem , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Evolução Fatal , Humanos , Granulomatose Linfomatoide/terapia , Masculino , Neoplasias da Medula Espinal/terapia , Adulto JovemRESUMO
Previous studies have indicated that bone morphogenetic protein-7 (BMP-7) is neuroprotective against cerebral ischemia/reperfusion (IR) injury. The present study was undertaken to determine the molecular mechanisms involved in this effect. Adult male Wistar rats were subjected to 2 h of transient middle cerebral artery occlusion (MCAO), followed by 24 h of reperfusion. BMP-7 (10-4 g/kg) or vehicle was infused into rats at the onset of reperfusion via the tail vein. Neurological deficits, infarct volume, histopathological changes, oxidative stress-related biochemical parameters, neuronal apoptosis, and apoptosis-related proteins were assessed. BMP-7 significantly improved neurological and histological deficits, reduced the infarct volume, and decreased apoptotic cells after cerebral ischemia. BMP-7 also markedly enhanced the activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and reduced the level of malondialdehyde (MDA) in IR rats. In addition, Western blot analysis indicated that BMP-7 prevented cytochrome c release, inhibited activation of caspase-3, caspase-9 and caspase-8. Our data suggested that BMP-7 has protective effects against cerebral IR injury in rats, and the neuroprotective effects may be attributed to attenuating oxidative stress and inhibiting neuronal apoptosis.
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Apoptose/efeitos dos fármacos , Proteína Morfogenética Óssea 7/farmacologia , Isquemia Encefálica/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/metabolismo , Animais , Isquemia Encefálica/patologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Malondialdeído/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Superóxido Dismutase/metabolismoRESUMO
To investigate the effect of mitochondrial heteroplasmy on embryo development, cloned embryos produced using bovine oocytes as the recipient cytoplasm and ovine granulosa cells as the donor nuclei were complemented with 2pL mitochondrial suspension isolated from ovine (BOOMT embryos) or bovine (BOBMT embryos) granulosa cells; cloned embryos without mitochondrial injection served as the control group (BO embryos). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and sodium bisulfite genomic sequencing were used to analyse mRNA and methylation levels of pluripotency genes (OCT4, SOX2) and mitochondrial genes (TFAM, POLRMT) in the early developmental stages of cloned embryos. The number of mitochondrial DNA copies in 2pL ovine-derived and bovine-derived mitochondrial suspensions was 960±110 and 1000±120, respectively. The blastocyst formation rates were similar in BOBMT and BO embryos (P>0.05), but significantly higher than in BOOMT embryos (P<0.01). Expression of OCT4 and SOX2, as detected by RT-qPCR, decreased significantly in BOOMT embryos (P<0.05), whereas the expression of TFAM and POLRMT increased significantly, compared with expression in BOOMT and BO embryos (P<0.05). In addition, methylation levels of OCT4 and SOX2 were significantly greater (P<0.05), whereas those of TFAM and POLRMT were significantly lower (P<0.01), in BOOMT embryos compared with BOBMT and BO embryos. Together, the results of the present study suggest that the degree of mitochondrial heteroplasmy may affect embryonic development.
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Bovinos , Clonagem de Organismos , Desenvolvimento Embrionário/genética , Mitocôndrias/genética , Técnicas de Transferência Nuclear/veterinária , Ovinos , Animais , Bovinos/embriologia , Bovinos/genética , Células Cultivadas , Quimera/genética , Quimera/metabolismo , Clonagem de Organismos/métodos , Clonagem de Organismos/veterinária , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/fisiologia , Epistasia Genética/fisiologia , Feminino , Dosagem de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genes Mitocondriais , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Ovinos/embriologia , Ovinos/genética , Especificidade da EspécieRESUMO
Graphitic carbon that allows reversible anion (de)intercalation is a promising cathode material for cost-efficient and high-voltage dual-ion batteries (DIBs). However, one notorious but overlooked issue is the incomplete interfacial anion desolvation, which not only reduces the oxidative stability of electrolytes, but also results in solvent co-intercalation into graphite layers. Here, an "anion-permselective" polymer electrolyte with abundant cationic quaternary ammonium motif is developed to weaken the PF6 - -solvent interaction and thus facilitates PF6 - desolvation. This strategy significantly inhibits solvent co-intercalation as well as enhances the oxidation resistance of electrolyte, ensuring the structural integrity of graphite. As a result, the as-assembled graphite||Li cell achieves a superior cyclability with an average Coulombic efficiency of 99.0% (vs 95.7% for baseline electrolyte) and 87.1% capacity retention after 2000 cycles even at a high cutoff potential of 5.4 V versus Li+ /Li. Besides, this polymer also forms a robust cathode electrolyte interface, working together to enable a long-life DIB. This strategy of tuning anion coordination environment provides a promising solution to regulate solvent co-intercalation chemistry for DIBs.
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Rechargeable magnesium (Mg) metal batteries are a promising candidate for "post-Li-ion batteries" due to their high capacity, high abundance, and most importantly, highly reversible and dendrite-free Mg metal anode. However, the formation of passivating surface film rather than Mg2+ -conducting solid electrolyte interphase (SEI) on Mg anode surface has always restricted the development of rechargeable Mg batteries. A stable SEI is constructed on the surface of Mg metal anode by the partial decomposition of a pristine Li electrolyte in the electrochemical process. This Li electrolyte is easily prepared by dissolving lithium tetrakis(hexafluoroisopropyloxy)borate (Li[B(hfip)4 ]) in dimethoxyethane. It is noteworthy that Mg2+ can be directly introduced into this Li electrolyte during the initial electrochemical cycles for in situ forming a hybrid Mg2+ /Li+ electrolyte, and then the cycled electrolyte can conduct Mg-ion smoothly. The existence of this as-formed SEI blocks the further parasitic reaction of Mg metal anode with electrolyte and enables this electrolyte enduring long-term electrochemical cycles stably. This approach of constructing superior SEI on Mg anode surface and exploiting novel Mg electrolyte provides a new avenue for practical application of high-performance rechargeable Mg batteries.
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The limited discharge capacity of LiCoO2 can be improved by increasing its working potential, but it suffers from Co4+ dissolution and decomposition of the electrolyte. Nitriles have attracted great interest as high-voltage electrolytes due to their wide electrochemical window. However, the cathodic interfacial stability of nitrile electrolytes with a high-voltage LiCoO2 cathode has yet to be explored. Herein, we adopted an SN-based deep eutectic electrolyte with SN as the only solvent and found that Co4+ could be reduced by the SN solvent on the interface of the LiCoO2 electrode, causing a reverse phase change of LiCoO2 and severe self-discharge of the LiCoO2|Li and LiCoO2|Li4Ti5O12 batteries. When LiDFOB was introduced into the electrolyte, the self-discharge behavior of cells could be largely decelerated. The series of characterizations performed in our work revealed that the cathode/electrolyte interface generated from the LiDFOB salt could stabilize the interface of LiCoO2 and suppress the dissolution of the ions of the transition metal Co.
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Over 150 million tons of high-alkaline bauxite residue was produced during the Bayer process of Bauxite smelting in the world annually, causing massive encroachment and irreversible pollution of soil. In this work, we proposed a new way out of bauxite residue, synthesizing a micro-electrolysis composite material (MECM) by carbothermal reduction of the bauxite residue towards the degradation of high-concentration organic wastewater. Batch experiments of organic compounds degradation were conducted to evaluate the performance of MECM with or without synergistic Fenton process. XRD and SEM-EDS analysis results indicated that a proper calcination temperature (1000â) could facilitate the generation and growth of zero-valent iron (ZVI), thereby forming a large number of galvanic cells with carbon, which could efficiently break the azo bonds. Additionally, the micro-electrolysis reaction of MECM could provide lots of Fe(â ¡), which constituted the Fenton system with the additional H2O2. In Fenton system, the aromatic rings and alkyl chains were further degraded and mineralized, which reduced the chemical oxygen demand (COD) of methyl orange (MO) from 450 to 54 mg/L. Therefore, the combination of the micro-electrolysis and Fenton process provides a clean and efficient method for the treatment of organic wastewater, which is a promising way out for bauxite residue.
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Melanoma is an aggressive skin carcinoma with poor prognosis, and is prevalent worldwide. It was demonstrated that microRNA (miR)21 and mitogenactivated protein kinase kinase 3 (MKK3) both participated in the occurrence and development of various tumors; however, their detailed roles in the progression of melanoma remain unclear. Reverse transcriptionquantitative PCR (RTqPCR) and western blot analyses were conducted to examine the expression levels of miR21 and MKK3 in clinical specimens of patients with melanoma and melanoma cell lines. A dualluciferase reporter assay was performed to verify the target interaction between miR21 and MKK3. The mRNA and protein expressions of MKK3 were measured using RTqPCR and western blot analysis, respectively, following transfection with miR21 mimics and inhibitor. Subsequently, Cell Counting Kit8 and colony formation assays, and flow cytometry were conducted to assess the effects of miR21 and MKK3 on the cell growth of melanoma. Cell migration and invasion experiments were performed to evaluate the effects of miR21 and MKK3 on the cell metastasis of melanoma. It was revealed that MKK3 was upregulated, and miR21 was downregulated in patients with melanoma and melanoma cell lines. MKK3 was demonstrated to be a direct target of miR21. Furthermore, it was demonstrated that upregulated miR21 expression and downregulated MKK3 expression suppressed cell proliferation and colony formation, promoted apoptosis, delayed the cell cycle, and inhibited cell migration and invasion. The present findings suggested that miR21 could inhibit the cell growth and metastasis of melanoma by negatively regulating MKK3.
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Carcinogênese/genética , MAP Quinase Quinase 3/genética , Melanoma/genética , MicroRNAs/genética , Adulto , Idoso , Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , PTEN Fosfo-Hidrolase/genéticaRESUMO
We report a strategy employing a concentrated electrolyte to boost the cycling stability of LiCoO2/graphite cells at 90 °C for the first time. Such a concentrated electrolyte provides the cells with superb cycling stability (97% after 160 cycles) at 90 °C. Further investigations unveil that the concentrated electrolyte participates in the formation of a compact LiF-rich CEI layer, which effectively inhibits the decomposition of electrolyte solvent and the dissolution of Co2+, maintaining the structural integrity of the LiCoO2 cathode.
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Highly reductive magnesium borohydride [Mg(BH4)2] is compatible with metallic Mg, making it a promising Mg-ion electrolyte for rechargeable Mg batteries. However, pure Mg(BH4)2 in ether-based solutions displays very limited solubility (0.01 M), low oxidative stability (<1.8 V vs Mg), and nucleophilic characteristic, all of which preclude its practical utilization for any battery applications. Herein, we present a multifunctional additive of tris(2 H-hexafluoroisopropyl)borate (THFPB) for preparing Mg(BH4)2-based electrolytes. By virtue of the strong electron-acceptor ability of the THFPB molecule, a transparent and high-concentration Mg(BH4)2/THFPB-diglyme (DGM) electrolyte (0.5 M, almost 50 times higher than that of the pristine Mg(BH4)2-DGM electrolyte) is first obtained, which shows dramatic performance improvements, including high ionic conductivity (3.72 mS cm-1 at 25 °C) and high Mg plating/stripping Coulombic efficiency (>99%). The newly-generated active cation and anion species revealed by Raman, NMR and MS spectra, increase the electrochemical potential window from 1.8 V to 2.8 V vs Mg on stainless steel electrode, rendering electrolytes the ability to examine high voltage cathodes. More importantly, on account of the non-nucleophilicity of active electrolyte species, we present the first example of magnesium-sulfur (Mg-S) batteries using Mg(BH4)2-based electrolytes, which exhibit a high discharge capacity of 955.9 and 526.5 mA h g-1 at the initial and 30th charge/discharge cycles, respectively. These achievements not only provide an efficient and specific strategy to eliminate the major roadblocks facing Mg(BH4)2-based electrolytes but also highlight the profound effect of functional additives on the electrochemical performances of unsatisfied Mg-ion electrolytes.
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Redox mediators (RMs) have been widely applied to reduce the charge overpotential of nonaqueous lithium-oxygen (Li-O2) batteries. Among the reported RMs, LiI is under hot debate with lots of controversial reports. However, there is a limited understanding of the charge mechanism of I- in anhydrous Li-O2 batteries. Here, we study the chemical reactivity between the oxidized state of I- and Li2O2. We confirm that the Li2O2 particles could be chemically oxidized by I2 rather than I3- species. Furthermore, our work demonstrates that the generated I- from Li2O2 oxidation would combine with I2 to give I3- species, hindering further oxidation of Li2O2 by I2. To improve the working efficiency of I- RMs, we introduce a compound LiI(3-hydroxypropionitrile)2 (LiI(HPN)2) with a high binding ability of I-. Compared with LiI, the cell that contained LiI(HPN)2 shows a significantly increased amount of I2 species during charge and enhanced Li2O2 oxidation efficiency under the same working conditions.
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Maternal effect genes encode proteins that are produced during oogenesis and play an essential role during early embryogenesis. Genetic ablation of such genes in oocytes can result in female subfertility or infertility. Here we report a newly identified maternal effect gene, Nlrp2, which plays a role in early embryogenesis in the mouse. Nlrp2 mRNAs and their proteins (â¼118 KDa) are expressed in oocytes and granulosa cells during folliculogenesis. The transcripts show a striking decline in early preimplantation embryos before zygotic genome activation, but the proteins remain present through to the blastocyst stage. Immunogold electron microscopy revealed that the NLRP2 protein is located in the cytoplasm, nucleus and close to nuclear pores in the oocytes, as well as in the surrounding granulosa cells. Using RNA interference, we knocked down Nlrp2 transcription specifically in mouse germinal vesicle oocytes. The knockdown oocytes could progress through the metaphase of meiosis I and emit the first polar body. However, the development of parthenogenetic embryos derived from Nlrp2 knockdown oocytes mainly blocked at the 2-cell stage. The maternal depletion of Nlrp2 in zygotes led to early embryonic arrest. In addition, overexpression of Nlrp2 in zygotes appears to lead to normal development, but increases blastomere apoptosis in blastocysts. These results provide the first evidence that Nlrp2 is a member of the mammalian maternal effect genes and required for early embryonic development in the mouse.
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Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Proteínas/genética , Proteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apoptose , Proteínas Reguladoras de Apoptose , Blastocisto/citologia , Blastocisto/metabolismo , Linhagem Celular , Embrião de Mamíferos/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Espaço Intracelular/metabolismo , Masculino , Camundongos , Oócitos/citologia , Oócitos/metabolismo , Partenogênese , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Zigoto/citologia , Zigoto/metabolismoRESUMO
Somatic cell cloning (nuclear transfer) is a technique through which the nucleus (DNA) of a somatic cell is transferred into an enucleated oocyte for the generation of a new individual, genetically identical to the somatic cell donor. It could be applied for the enhancement of reproduction rate and the improvement of food products involving quality, yield and nutrition. In recent years, the United States, Japan and Europe as well as other countries announced that meat and milk products made from cloned cattle are safe for human consumption. Yet, cloned animals are faced with a wide range of health problems, with a high death rate and a high incidence of disease. The precise causal mechanisms for the low efficiency of cloning remain unclear. Is it safe that any products from cloned animals were allowed into the food supply? This review focuses on the security of meat, milk and products from cloned cattle based on the available data.