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Transition metal oxides (TMOs) have excellent electrochemical properties. However, they are commonly associated with short cycle lives, agglomeration, and lower electrical conductivity. To ameliorate these drawbacks, porous rod-shaped CuO@Co3O4 has been synthesized through calcination with optimized oxidation temperature by using CuCo-MOF-74 as a template. Due to the porous structure, the CuO@Co3O4 electrode significantly increases the contact area with the electrolyte and greatly improves the reaction kinetics. As a result, the CuO@Co3O4 electrode exhibits excellent electrochemical performance with a specific capacitance of 545.5 F g−1 at a current density of 1 A g−1. The capacitance retention at 10 A g−1 was 88.7% after 10 000 cycles. Furthermore, an asymmetric supercapacitor (SC) has been assembled with CuO@Co3O4 as the positive electrode and commercial reduced graphene oxide (RGO) as the negative electrode, and the device has exhibited an energy density of 38.2 W h kg−1 at a power density of 1268.3 W kg−1. Impressively, the capacitance retention remained 83.2% even after 10 000 cycles at a high current density of 10 A g−1. This performance has demonstrated the potential of CuO@Co3O4 as an anode material for SCs. [ABSTRACT FROM AUTHOR]

Atomically dispersed metal catalysts (ADMCs) have attracted increasing interest in the field of heterogeneous catalysis. As sub-nanometric catalysts, ADMCs have exhibited remarkable catalytic performance in many reactions. ADMCs are classified into two categories: single atom catalysts (SACs) and atomically dispersed clusters with a few atoms. To stabilize the highly active ADMCs, nanodiamond (ND) and its derivatives (NDDs) are promising supports. In this Feature Article, we have introduced the advantages of NDDs with a highly curved surface and tunable surface properties. The controllable defective sites and oxygen functional groups are known as the anchoring sites for ADMCs. Tunable surface acid–base properties enable ADMCs supported on NDDs to exhibit unique selectivity towards target products and an extended lifetime in many reactions. In addition, we have firstly overviewed the recent advances in the synthesis strategies for effectively fabricating ADMCs on NDDs, and further discussed how to achieve the atomic dispersion of metal precursors and stabilize the as-formed metal atoms against migration and agglomeration based on NDDs. And then, we have also systematically summarized the advantages of ADMCs supported on NDDs in reactions, including hydrogenation, dehydrogenation, aerobic oxidation and electrochemical reaction. These reactions can also effectively guide the design of ADMCs. The recent progress in understanding the effect of structure of active centers and metal–support interactions (MSIs) on the catalytic performance of ADMCs is particularly highlighted. At last, the possible research directions in ADMCs are forecasted. [ABSTRACT FROM AUTHOR]

Peracetic acid (PAA) is an effective oxidant capable of solubilising lignin and efficiently depolymerising it to selective phenolic compounds; however, the specific role by which PAA initiates the depolymerisation is still elusive. Herein, interaction between PAA and the lignin macromolecule and the consequent structural changes of the latter were studied by characterising the lignin packing structure and its associated changes during the oxidation process. While the lignin packing structure and its changes associated with the PAA-mediated oxidation were probed by X-ray diffraction, the impact of the PAA on different chemical functionalities present in the lignin structure was established by 13C and 1H–13C heteronuclear single-quantum coherence nuclear magnetic resonance (NMR) spectroscopy. Combining the NMR spectroscopy results, and the product distribution, we conclude that the predominant reaction pathway for the oxidative depolymerisation of lignin with PAA is the Baeyer–Villiger oxidation of the ketone formed by the oxidation of the benzylic hydroxyl group adjacent to the β-O-4 linkage. The experimental evidence provided herein corroborated that PAA instigates oxygen insertion to the lignin macromolecule resulting in disruption of its packing structures and facilitates depolymerisation. We also investigated various metal oxide and mixed metal oxide catalysts to identify effective catalysts that further enhance the efficiency of PAA-mediated depolymerisation of lignin and produce selective monomeric phenolic compounds. Techno-economic analysis was also conducted to identify the key parameters associated with this oxidative process that need to be considered for possible commercial application. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) contamination during fuel ethanol fermentation can lead to significant economic loses. To circumvent this, fuel ethanol plants add antibiotics prophylactically, but their overuse has resulted in the emergence of antibiotic-resistant LAB strains. Lignin is a sustainable biopolymer that can be found as a waste product from lignocellulosic biorefineries. Technical lignins and their smaller phenolic subunits have been shown to exhibit broad-spectrum antimicrobial properties, but there is a lack of demonstrations of lignin derivatives with highly selective properties in the literature. Here, corn stover lignin from a biorefinery was oxidatively depolymerized using an environmentally benign organic oxidant, peracetic acid, into a bio-oil that has selective antimicrobial properties against LAB and not yeasts. The resulting bio-oil demonstrated up to 90% inhibition of commercially sampled LAB (including antibiotic-resistant strains) at 4 mg ml−1 with no inhibition against an industrial yeast strain. These antimicrobial properties of the bio-oil are attributed to larger unidentified lignin oligomers, compared to monolignols, that have a membrane damaging mode of action. Using the bio-oil (4 mg ml−1) during simultaneous saccharification and fermentation (SSF) of raw corn starch showed no inhibition of enzymatic activity, and in LAB contaminated fermentations the bio-oil treatments showed an 8% increase in ethanol yields at higher bacterial contamination ratios (l : 100 yeast to LAB, CFU per ml). This study illustrates the efficacy of using lignin bio-oil as an antibiotic replacement during fuel ethanol fermentation and demonstrates the highly selective antimicrobial properties of lignin oligomers, which creates a viable lignin valorization strategy for biorefineries. [ABSTRACT FROM AUTHOR]

Exploiting highly active and low-cost electrocatalysts is imperative and challenging for developing advanced energy storage and conversion devices. Herein, we report a core–shell structured carbon hybrid (PNC@CoNC) as an effective bifunctional oxygen catalyst prepared by a surface polymerization strategy and a subsequent pyrolysis process, consisting of nanoporous N-doped carbon core carbonized from ZIF-8 and N-doped graphitic carbon shell with embedded Co nanoparticles carbonized from the cobalt ion-doped polydopamine coating layer. The desirable nanoarchitecture endows the hybrid with a high specific surface area of 531 m2 g−1, high conductivity, abundant micro-/meso-pores and electrocatalytically active N-dopant species. As a result, the hybrid PNC@CoNC displays a positive half-wave potential of 0.81 V towards oxygen reduction and a low overpotential of 490 mV at 10 mA cm−2 towards oxygen evolution in alkaline electrolytes, as well as excellent electrochemical stability. The bifunctional oxygen activity is comparable with that of the commercial catalysts and the recently reported electrocatalysts. Expectedly, as an air–electrode catalyst in rechargeable Zn–air battery (ZAB), PNC@CoNC shows a high power density of 130 mW cm−2, a low charge/discharge voltage gap, and superior cycling stability. Additionally, the as-prepared hybrid also shows promising application potential in solid-state ZAB. Therefore, this work provides a lesson for the synthesis of non-noble metal electrocatalysts in advanced new energy devices. [ABSTRACT FROM AUTHOR]

Biorefineries valorize waste biomass to biofuels and bioproducts, but the associated wastewater treatment is costly and energy-intensive. This study demonstrates that not only the recalcitrant black liquor generated from biorefineries can be treated using a microbial electrochemical process, but also value-added materials including lignin, chemicals, and H2 can be separated to enable resource recovery. A lab scale microbial biomass recovery cell (MBRC) was developed to treat the actual black liquor from the deacetylation and mechanical refining (DMR) process, and the results show that 60.1–73.8% of organics, 52.0–54.6% of salts, and 30.8–49.5% of lignin were removed using different operational modes. Moreover, by utilizing the unique pH gradient generated between the different reactor chambers, tailored recoveries of lignin, chemicals, and H2 were realized for the first time. The recoveries of lignin and salts were up to 61.2 ± 2.7% and 92.2 ± 1.6%, respectively. Ion transfer and organic transformation were further analyzed to understand the reaction mechanisms and improve the system performance. [ABSTRACT FROM AUTHOR]

A catalytic process, involving the hydrodeoxygenation (HDO) of dilute alkali extracted corn stover lignin catalysed by noble metal catalyst (Ru/Al2O3) and acidic zeolite (H+-Y), to produce lignin-substructure-based hydrocarbons (C7–C18), primarily C12–C18 cyclic structure hydrocarbons in the jet fuel range, was demonstrated. [ABSTRACT FROM AUTHOR]

A visible-light-induced directed decarboxylative disulfuration of α-keto acids and oxamic acids was developed. As a result, a series of versatile mono acyl disulfide derivatives was synthesized under mild and sustainable reaction conditions. This protocol has a broad substrate scope, good functional-group tolerance, and excellent synthetic applications.

Ovarian cancer is one of the leading causes of death from gynecologic malignancy in women. High-grade serous carcinomas, low-grade serous carcinomas, endometrioid carcinomas, clear cell carcinomas, and mucinous carcinomas with distinct pathological and clinical characteristics are the main histological subtypes of ovarian cancer. The majority of ovarian cancer patients are diagnosed at an advanced stage due to a lack of suitable screening tests for early detection and specific early symptoms. Despite progress in therapy improvements in ovarian cancer, most patients develop a recurrence within months or years after initial treatment. Given that the presence of tumor infiltrating lymphocytes is associated with prognosis and ovarian cancer is among the first cancers with an established association of immune cell infiltration, identification of the immune microenvironment in ovarian cancer is thought to be promising. In this study, to increase the understanding of tumor immune cell interactions, we undertook a study of tumor infiltrating lymphocytes in a large group of ovarian cancer patients. Our results suggested that tumor immune infiltrates of ovarian cancer were quite cohort and subtype dependent, and activated CD4+ T and CD8+ T tumor infiltrating lymphocytes were associated with good overall survival in the high-grade serous tumors. We found that high expression levels of the immune-related genes were associated with good prognosis in high-grade serous carcinomas. In addition, two different groups of prognostic genes were found in the high-grade and low-grade serous carcinomas, indicating that these two subtypes of serous carcinomas were two biologically and clinically different cancer types.

MicroRNAs (miRNAs) are a class of small non-coding RNA genes that post-transcriptionally regulate gene expression. With the development of high-throughput miRNA detection technology, researchers have begun to investigate the relationships between miRNA expression and its functions. In this study, we systematically analyzed the underlying molecular mechanisms and biological functions of co-expressed miRNAs. By integrating miRNA expression profiles, miRNA genome locations, transcriptional factors (TFs) of miRNAs and their target genes, we concluded that co-expressed miRNAs are more likely to be located in the same miRNA cluster (p = 6.05 x 10(-30)), are regulated by more common TFs (p = 9.17 x 10(-17)) and have consistent functions (p = 1.01 x 10(-6)). Moreover, among the top 10% (84) co-expressed miRNA pairs that are located on the same chromosomes, 37 miRNA pairs are located in the same cluster. Of the remaining 47 pairs, 36 miRNA pairs share more common TFs (>7). They account for 73/84 (86.9%) of total miRNA pairs. Finally, we further analyzed the top 10 co-expressed miRNA pairs. Almost all of these miRNA pairs are located in the same cluster, are regulated by many common TFs and have highly consistent functions, in agreement with previous reports. Thus, our study may provide an important reference for miRNA regulations and functions.