The visible-light-driven CO 2 reduction efficiency is largely restrained by the negative photoabsorption and high recombination rate of electron−hole pairs. It is an effective method to increase the efficiency of CO 2 photoreduction by doping alkali metal elements to engineer the electronic properties of the catalyst. Here, we report a new study on the potassium-doped g-C 3 N 4 (K-CN) being used for CO 2 reduction irradiated by visible light. DFT calculations and XPS tests show that the potassium doping is interlayer doping, changing the electronic structure of g-C 3 N 4 . The higher I D /I G value indicates more structural distortion and defects caused by K doping. K-CNs have enhanced visible-light absorption, and PL spectra demonstrate that the introduction of potassium advances the separation and transmission of photoexcited charge carriers, further confirmed by transient photocurrent response experiment. Under visible light, K-CN-7 achieved efficient CO 2 reduction without any noble metal as a cocatalyst, with CO formation rates of 8.7 μmol g −1 h −1 , which is 25 times that of ordinary g-C 3 N 4 . Our work further validates the importance of inhibiting e − /h + recombination in improving solar energy conversion efficiency while also bringing hope for efficient solar fuel production using g-C 3 N 4 . KEYWORDS: g-C 3 N 4 , CO 2 photoreduction, potassium doping, first-principles calculations, photocatalysis

Polycystic ovary syndrome (PCOS) is a very common, complex, and heterogeneous endocrine disorder of women that involves a combination of environmental and genetic factors. PCOS affects women of growing age particularly at the early to late reproductive stage (15–35 years). Currently, PCOS affects 1 in every 10 women worldwide. It is characterized majorly by a raised level of androgens such as testosterone and a large number of ovarian cysts (more than 10) that cause anovulation, infertility, and irregular menstrual cycle. PCOS is also related to other endocrine and metabolic abnormalities, such as obesity, hirsutism, acne, diabetes, insulin resistance, and glucose impairment. PCOS can be treated with allopathic, ayurvedic, and natural or herbal medications along with lifestyle modifications. Herbal medicines remained in demand for numerous reasons such as high cost and side effects associated with the use of allopathic medicine and our traditional norms, which have helped humans to use more herbal products for their health benefits. Estrogenic and nonestrogenic phytochemicals present in various plant species such as Glycyrrhiza glabra L. [Fabaceae], Aloe vera (L.) Burm. f. [Asphodelaceae], Silybum marianum (L.). Gaertn. [Asteraceae], Serenoa repens (W.Bartram) Small [Arecaceae], Actaea racemosa L. [Ranunculaceae], and Angelica sinensis (Oliv.) Diels [Apiaceae] are effective and harmless. Herbal medicines are found to be cost-effective, efficacious, and a highly esteemed source of management/treatment for PCOS than allopathic medicines. In this literature review, diagnosis, signs, and symptoms of PCOS; causes of hormonal imbalance; and risk factors associated with PCOS and their management are discussed briefly, and the focus was to find out the role of herbal remedies in PCOS management.

We report the observation by angle-resolved photoemission spectroscopy of an impurity state located inside the superconducting gap of Ba 0.6 K 0.4 Fe 2 As 2 and vanishing above the superconducting critical temperature, for which the spectral weight is confined in momentum space near the Fermi wave-vector positions. We demonstrate, supported by theoretical simulations, that this in-gap state originates from weak scattering between bands with opposite sign of the superconducting-gap phase. This weak scattering, likely due to off-plane nonmagnetic (Ba, K) disorder, occurs mostly among neighboring Fermi surfaces, suggesting that the superconducting-gap phase changes sign within holelike (and electronlike) bands. Our results impose severe restrictions on the models promoted to explain high-temperature superconductivity in these materials.

Comprehensive studies of the electronic states of Ir 5d and Te 5p have been performed to elucidate the origin of the structural phase transition in IrTe 2 by combining angle-resolved photoemission spectroscopy and resonant inelastic X-ray scattering. While no considerable changes are observed in the configuration of the Ir 5d electronic states across the transition, indicating that the Ir 5d orbitals are not involved in the transition, we reveal a van Hove singularity at the Fermi level (E F ) related to the Te p x +p y orbitals, which is removed from E F at low temperatures. The wavevector connecting the adjacent saddle points is consistent with the in-plane projection of the superstructure modulation wavevector. These results can be qualitatively understood with the Rice-Scott "saddle-point" mechanism, while effects of the lattice distortions need to be additionally involved.

Microbes with complex functions have been found to be a potential component in tumor microenvironments. Due to their low biomass and other obstacles, intratumor microbiota is poorly understood. Mucosal sites and normal adjacent tissues are important sources of intratumor microbiota, while hematogenous spread also leads to the invasion of microbes. Intratumor microbiota affects the progression of tumors through several mechanisms, such as DNA damage, activation of oncogenic pathways, induction of immunosuppression, and metabolization of drugs. Notably, in different types of tumors, the composition and abundance of intratumor microbiota are highly heterogeneous and may play different roles in the progression of tumors. Because of the concern in this field, several techniques such as omics and immunological methods have been used to study intratumor microbiota. Here, recent progress in this field is reviewed, including the potential sources of intratumor microbiota, their functions and related mechanisms, and their heterogeneity. Techniques that can be used to study intratumor microbiota are also discussed. Moreover, research is summarized into the development of strategies that can be used in antitumor treatment and prospects for possible future research in this field.

By employing CuOAc as the catalyst, we realize a four-component reaction of 1,3-enynes, diselenides, DABCO·(SO2)2, and cycloketone oxime esters, providing facile access to diverse cyanoalkylsulfonylated allenyl selenides in moderate to good yields. This reaction features high functional group tolerance and a broad substrate scope, enabling the regioselective, sequential formation of C–SO2 and C–Se bonds under mild reaction conditions. Moreover, the utility of this methodology is further illustrated through the late-stage functionalization of drug-based molecules.

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From the viewpoint of synthetic accessibility and functional group compatibility, photoredox-catalyzed sulfur dioxide insertion strategy enables in situ generation of functionalized sulfonyl radicals from easily accessible starting materials under mild conditions, thereby conferring broader application potential. Here we present two complementary photoinduced sulfur dioxide insertion systems to trigger radical asymmetric Truce–Smiles rearrangements for preparing a variety of chiral sulfones that bear a quaternary carbon stereocenter. This protocol features broad substrate scope and excellent stereospecificity. Aside from scalability, the introduction of a quaternary carbon stereocenter at position β to bioactive molecule-derived sulfones further demonstrates the practicality and potential of this methodology.