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The efficient hydrogenation of biomass-derived levulinic acid (LA) to value-added γ-valerolactone (GVL) based on nonprecious metal catalysts under mild conditions is crucial challenge because of the intrinsic inactivity and instability of these catalysts. Herein, a series of highly active and stable carbon-encapsulated Co/ZnO@C-X (where X = 0.1, 0.3, 0.5, the molar ratios of Zn/(Co+Zn)) heterojunction catalysts were obtained by in situ pyrolysis of bimetal CoZn MOF-74. The optimal Co/ZnO@C-0.3 catalyst could achieve 100% conversion of LA and 98.35% selectivity to GVL under mild conditions (100 °C, 5 bar, 3 h), which outperformed most of the state-of-the-art catalysts reported so far. Detailed characterizations, experimental investigations, and theoretical calculations revealed that the interfacial interaction between Co and ZnO nanoparticles (NPs) could promote the dispersibility and air stability of the active Co

Background Spinocerebellar ataxia type 1 (SCA1) is the third most common type of spinocerebellar ataxia in China. However, data about Chinese SCA1 patients are limited. This study aims to provide a detailed description of the phenotype and genotype of Chinese SCA1 individuals and guide the clinical practice. Methods A total of 110 SCA1 individuals from 79 pedigrees and 123 unrelated normal controls were recruited. Sanger sequencing, SfaNI restriction and TA cloning were used for the determination of the CAG repeat size and the intrinsic structure. Clinical data including scale scores, magnetic resonance imaging and electromyography were collected. Results Interrupted pathogenic alleles occurred in 5.5% of the SCA1 individuals and caused later disease onset (p

Carbon-encapsulated metal-organic framework (MOF) composite is one kind of emerging new catalyst with high efficiency and has gained much attention. However, for this kind of composite catalyst, the key to improving its catalytic activity and durability is to realize the effective dispersion of MOF nanoparticles (NPs) and enhance the interaction between MOF NPs and the carbon matrix, which remain a significant challenge. Herein, ultrafine MOF NPs within multichamber carbon spheres (MOF@MCCS), for the first time, have been rationally synthesized by a two-step double-solvent strategy for high-performance catalysts. The precise loading of guest MOFs can be achieved by adjusting the multichamber structure and calcination extent of the multichamber polymer (MCP), and the particle size of MOFs can be as low as 13.2 nm. Due to the formation of abundant carbon defects in the pyrolysis process of MCPs, the special structure and synergistic effect make the material exhibit higher catalytic activity and durability. More importantly, this method is universal and can be extended to different MOF systems. The two-step double-solvent strategy not only prepares a unique structure of MOF@MCCS-type host-guest-encapsulated catalysts but also provides a new idea for the design of high-efficiency catalysts with better performance and higher durability.

The development of low-cost, highly active and stable electrocatalysts for the oxygen evolution reaction (OER) is desirable and challenging. In this work, we report nickel foam (NF) supported low-crystalline NiCoFe nanosheet array electrocatalysts derived from NiCo layered double hydroxide via spontaneous cation exchange reaction. Driven by the redox properties of NiCo layered double hydroxide and iron salt precursors, the entire cation exchange reaction process is completed without extra energy input. The chemical composition and catalytic properties of the as-prepared NiCoFe/NF catalysts are strongly dependent on the valence state of the Fe cation in the iron salt precursors. The NiCoFe/NF–FeSO4 catalyst with FeSO4 as the iron salt precursor exhibits satisfactory OER activity with a much lower overpotential of 293 mV to reach a current density of 100 mA cm−2 as compared with NiCoFe/NF–Fe2(SO4)3 (η100 = 333 mV), NiCo/NF (η100 = 425 mV) and commercial RuO2 (η100 = 399 mV) catalysts. Moreover, NiCoFe/NF–FeSO4 also exhibits impressive long-term durability for the OER. The current density remains nearly unchanged during the 95 h of continuous OER test, demonstrating a promising application in actual industrial water electrolysis. These findings indicate that the iron ion valence states in the iron salt precursors have a significant impact on the composition of the catalysts and thus affect their catalytic performances. This work is instructive for the rational design and preparation of highly efficient Earth-abundant electrocatalysts for the OER.

Introduction Due to diverse symptoms of spinocerebellar ataxia type 3 (SCA3) and the high prevalence of SCA3 in China, a more in-depth study of Chinese SCA3 patients in a large cohort is well merited. Methods During the last 10 years, 730 patients and 133 premanifest individuals from 667 SCA3 families genetically confirmed to have SCA3 were enrolled from three leading academic hospitals in China. The clinical profile and genotype-phenotype correlation were analyzed. Results A quadratic equation best explained the relationship between the logarithmically transformed age at onset (AAO) and expanded CAG repeats (expCAGs) (r2 = 0.634, p 10 years. Intriguingly, onset after parturition happened in 10 female patients with the AAO of 26.7 ± 4.3 years and the expCAG of 77.4 ± 1.4 repeats. Five out of 12 patients with subtype V and larger expCAGs (78.8 ± 4.8 repeats) suffered from spastic gait initially, and 10 out of 12 showed no limb ataxia. Nystagmus happened most frequently (10.5%) in premanifest individuals. Conclusion We demonstrated the genotype-phenotype correlation in the largest cohort of SCA3 individuals to date, and interestingly found some new phenomena in Chinese SCA3 individuals.

Spinocerebellar ataxia type 3 (SCA3) is caused by unstable expanded CAG repeats (expCAGs) in ATXN3. Factors associated with intergenerational instability (delta-expCAG) and genetic anticipation in SCA3 have never been reported in Chinese mainland. Here, we demonstrated that unstable transmissions occurred more often in sons than in daughters (91% vs 72%, Fisher’s exact test, p = 0.012). The extended delta-expCAG of father-son transmissions was greater than that of mother-son transmissions (3.8 ± 2.3 repeats vs 1.6 ± 1.0 repeats, Mann-Whitney U, p = 0.001). Genetic anticipation was frequently observed between generations but not affected by the delta-expCAG.

Background Although many causative genes have been uncovered in recent years, genetic diagnosis is still missing for approximately 50% of autosomal recessive cerebellar ataxia (ARCA) patients. Few studies have been performed to determine the genetic spectrum and clinical profile of ARCA patients in the Chinese population. Methods Fifty-four Chinese index patients with unexplained autosomal recessive or sporadic ataxia were investigated by whole-exome sequencing (WES) and copy number variation (CNV) calling with ExomeDepth. Likely causal CNV predictions were validated by CNVseq. Results Thirty-eight mutations including 29 novel ones were identified in 25 out of the 54 patients, providing a 46.3% positive molecular diagnostic rate. Ten different genes were involved, of which four most common genes were SACS, SYNE1, ADCK3 and SETX, which accounted for 76.0% (19/25) of the positive cases. The de novo microdeletion in SACS was reported for the first time in China and the uniparental disomy of ADCK3 was reported for the first time worldwide. Clinical features of the patients carrying SACS, SYNE1 and ADCK3 mutations were summarized. Conclusions Our results expand the genetic spectrum and clinical profiles of ARCA patients, demonstrate the high efficiency and reliability of WES combined with CNV analysis in the diagnosis of suspected ARCA, and emphasize the importance of complete bioinformatics analysis of WES data for accurate diagnosis.

Background and ObjectivesFew biochemical markers have been identified in spinocerebellar ataxia type 2 (SCA2). This study aimed to determine the levels of neurofilament light (NfL) in patients with SCA2 and to identify whether they are associated with disease severity.MethodsParticipants were recruited from 1 medical center in China, and individuals with SCA2 were genetically diagnosed. NfL levels were assessed with the single molecule array method. Disease severity was evaluated with the Scale for the Assessment and Rating of Ataxia (SARA), the International Cooperative Ataxia Rating Scale (ICARS), and the Inventory of Non-Ataxia Symptoms (INAS). Cerebellum and brainstem volumes were calculated from neuroimaging measurements. We used the Pearson correlation and partial correlation for correlation analyses.ResultsForty-nine patients with manifest SCA2, 10 preclinical individuals with SCA2, and 92 controls were enrolled. A high consistency was identified between serum and CSF NfL (r = 0.868, p < 0.0001). In individuals with SCA2, levels of serum NfL were associated with disease severity (SARA: r = 0.425, p = 0.003; ICARS: r = 0.383, p = 0.009; INAS:, r = 0.390, p = 0.007; cerebellum volume: r = −0.393, p = 0.024) after adjustment for age. NfL levels were higher close to the expected age at onset in preclinical individuals with SCA2 (R2 = 0.43, p = 0.04).DiscussionLevels of serum NfL were correlated with disease intensity in individuals with SCA2 and were higher close to the estimated age at onset in preclinical SCA2. Therefore, NfL is a potential serum biomarker of disease severity in SCA2.Classification of EvidenceThis study provides Class II evidence that elevated NfL levels are associated with disease severity in individuals with SCA2.

Spinocerebellar ataxia type 3 (SCA3) is caused by unstable expanded CAG repeats (expCAGs) in ATXN3. Factors associated with intergenerational instability (delta-expCAG) and genetic anticipation in SCA3 have never been reported in Chinese mainland. Here, we demonstrated that unstable transmissions occurred more often in sons than in daughters (91% vs 72%, Fisher's exact test, p = 0.012). The extended delta-expCAG of father-son transmissions was greater than that of mother-son transmissions (3.8 ± 2.3 repeats vs 1.6 ± 1.0 repeats, Mann-Whitney U, p = 0.001). Genetic anticipation was frequently observed between generations but not affected by the delta-expCAG.