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1.
Artigo em Inglês | MEDLINE | ID: mdl-36078362

RESUMO

Due to the fast growth of China's economy, urban atmospheric pollution has become a serious problem affecting the public's physical and mental health. The '2 + 26' cities, as the Jing-Jin-Ji atmospheric pollution transmission channel, has attracted widespread concern. There were several previous studies on the economic loss of public health caused by PM2.5 pollution in '2 + 26' cities. To assess the economic loss caused by PM2.5 on human health in '2 + 26' cities, this paper used the exposure-response model, the health effect loss model and willingness to pay method to obtain the economic loss from PM2.5 pollution with the latest available data in 2020. It was concluded that, in 2020, the economic loss of '2 + 26' cities from PM2.5 was spatially distributed low in the east and high in the west. In addition, it was larger in the southern and northern part, which was smaller in the middle of the region. Based on the conclusions, policy recommendations were put forward.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Monitoramento Ambiental , Humanos , Material Particulado/análise , Saúde Pública
2.
Dalton Trans ; 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36149342

RESUMO

Two nanosized titanium-oxide clusters (TOCs), Ti12(µ2-O)14(µ3-O)4PA16 (1; PA = 2-picolinate) and Ti12(µ2-O)18PA18 (2) were synthesized by using 2-picolinic acid and Ti(OiPr)4 in one-pot reactions. Their structures were determined using single-crystal X-ray diffractometry. Although both have the same core composition of Ti12O18, 1 exhibited superior H2 evolution activity of up to 180 µmol h-1 g-1, which is nearly eight times faster than 2. Mechanism studies revealed that 1 could induce the assembly of 2.3 nm PtNPs into 10-30 nm supra-nanoparticle structures, which contributed to the increased H2 evolution rate.

3.
Langmuir ; 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130147

RESUMO

This study numerically investigates the effects of the Weber number (We) and cylinder-to-droplet radius ratio (R*) on the impact dynamics of a low-viscosity droplet on a hydrophobic cylinder by the lattice Boltzmann method. The intrinsic contact angle of the surface is chosen as θ0 = 122°± 2°, which ensures a representative hydrophobicity. The regime diagram of the impact dynamics in the parameter space of We versus R* is established with categories of split and nonsplit regimes. The droplet would split during impact as α = We/R* exceeds a critical value. In the nonsplit regime, the droplet bounces off the cylinder at most Weber numbers unless the impact velocity is minuscule (We < 2). The contact time of the droplet on the cylinder surface decreases with increasing R* or decreasing We, indicating bouncing is facilitated under such conditions. This can be explained by the suppressed adhesion dissipation between the droplet and surface due to a reduction in the contact area. In the split regime, sufficient kinetic energy inside the impacting droplet determines whether the whole droplet could detach from the surface. With a small cylinder (R* < 0.83) and large We (>25), the adhesion effect is weakened for the side fragments because of the small contact area, and it facilitates the dripping of fragments. For other conditions, the detachment, especially for the tiny droplet on the cylinder top, only occurs if the deformation is prominent at We > 35. Moreover, the spreading dynamics of the impacting droplet are also highlighted in this work.

4.
Inorg Chem ; 61(37): 14887-14898, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36063420

RESUMO

The solvothermal reaction of titanium isopropoxide and chromate in the presence of benzoate produced two novel host-guest clusters encapsulating Cs+ or H3O+, (H3O)@Ti7Cr14 and Cs@Ti7Cr14. The most remarkable feature is that the Ti7O7 ring is concentrically embraced by a Cr14O14 ring to form a rigid Ti7Cr14 host. ESI-MS and 133Cs NMR revealed that the overall framework structures are preserved, whereas the benzoate ligands on the two clusters may be labile in solutions. Both (H3O)@Ti7Cr14 and Cs@Ti7Cr14 exhibit good UV-vis light-responsive properties and photocatalytic activities, with absorption edges extending up to 780 nm. Cs@Ti7Cr14 is an effective visible-light-responsive photocatalyst in both the heterogeneous methylene dye degradation and homogeneous CO2 cycloaddition reaction under mild conditions like room temperature and 1 bar of CO2. According to the mechanism studies, Cs+, as a rigid guest, can significantly improve the photogenerated charge separation efficiency of the Ti7Cr14 host, thereby improving its interface charge separation properties, photocurrent, and photocatalytic activities. Our findings not only provide new members of heterometallic titanium oxide clusters to enrich the metal oxide cluster family but also open up new possibilities for their photoresponses, which may play an important role in solar energy harvesting for sustainable chemistry.

5.
Sci Rep ; 12(1): 15196, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071133

RESUMO

Heavy metals released from kerogen to produced water during oil/gas extraction have caused major enviromental concerns. To curtail water usage and production in an operation and to use the same process for carbon sequestration, supercritical CO2 (scCO2) has been suggested as a fracking fluid or an oil/gas recovery agent. It has been shown previously that injection of scCO2 into a reservoir may cause several chemical and physical changes to the reservoir properties including pore surface wettability, gas sorption capacity, and transport properties. Using molecular dynamics simulations, we here demonstrate that injection of scCO2 might lead to desorption of physically adsorbed metals from kerogen structures. This process on one hand may impact the quality of produced water. On the other hand, it may enhance metal recovery if this process is used for in-situ extraction of critical metals from shale or other organic carbon-rich formations such as coal.

6.
BMJ Open ; 12(8): e056043, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038163

RESUMO

INTRODUCTION: Lung cancer was the most common malignancy and the leading cause of cancer-related death in China or worldwide, and surgery is still the preferred treatment for early-stage non-small cell lung cancer (NSCLC). The pattern of lymph node metastasis was found potentially lobe specific, and thus, lobe-specific lymph node dissection (L-SLND) was proposed to be an alternative to systematic lymph node dissection (SLND) for the treatment of early-stage NSCLC. METHODS AND ANALYSIS: The LobE-Specific lymph node diSsectiON trial is a single-institutional, randomised, double-blind and parallel controlled trial to investigate the feasibility of L-SLND in clinically diagnosed stage IA1-2 NSCLC with ground-glass opacity components (≥50%). The intraoperative frozen section examination of surgical tissues confirms the histological type of NSCLC. We hypothesise that L-SLND (experimental group) is not inferior to SLND (control group) and intend to include 672 participants for the experimental group and 672 participants for the control group with a follow-up duration of 60 months. The primary outcomes are 5-year disease-free survival and 5-year overall survival. The secondary outcomes are metastatic lymph node ratio, postoperative complication incidence and mortality, duration of operation, duration of anaesthesia (min), the volume of bleeding (mL) and drainage volume. The intention-to-treat analysis would be performed in the trial. ETHICS AND DISSEMINATION: This trial was approved by the ethics committee on biomedical research, West China Hospital of Sichuan University (2021-332). Informed consent would be obtained from all participants, and dissemination activities would include academic conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: This trial was registered in the Chinese Clinical Trial Registry, ChiCTR2100048415.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Intervalo Livre de Doença , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
J Am Chem Soc ; 144(33): 15275-15285, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35950969

RESUMO

The construction of diversely substituted all-carbon quaternary centers has been a longstanding challenge in organic synthesis. Methods that add three alkyl substituents to a simple C(sp3) atom rely heavily on lengthy multiple processes, which usually involve several preactivation steps. Here, we describe a straightforward three-step sequence that uses a range of readily accessible activated trichloromethyl groups as the carbon source, the three C-Cl bonds of which are selectively functionalized to introduce three alkyl chains. In each step, only a single C-Cl bond was cleaved with the choice of an appropriate Lewis base-boryl radical as the promoter. A vast range of diversely substituted all-carbon quaternary centers could be accessed directly from these activated CCl3 trichloromethyl groups or by simple derivatizations. The use of different alkene traps in each of the three steps enabled facile collections of a large library of products. The utility of this strategy was demonstrated by the synthesis of variants of two drug molecules, whose structures could be easily modulated by varying the alkene partner in each step. The results of kinetic and computational studies enabled the design of the three-step reaction and provided insights into the reaction mechanisms.


Assuntos
Alcenos , Carbono , Alcenos/química , Carbono/química , Técnicas de Química Sintética
9.
PLoS One ; 17(8): e0270952, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35913937

RESUMO

Rural subjects, the agricultural industrial structure, public services and rural governance are fully empowered by digital villages. This empowerment effectively compensates for the urban-rural digital divide and promotes the equalization of urban-rural income, consumption, education, medical care, and governance. Based on the three-stage data envelopment analysis (DEA) model and Malmquist index, this article conducts an in-depth study of the static and dynamic efficiency trends of digital villages that empower urban-rural balanced development in 31 provinces in China from 2015 to 2020. The results show that comprehensive technical efficiency of 31 provinces is weak DEA effective, and that the scale efficiency is the main factor affecting comprehensive technical efficiency. The educational level, local finance and industrial structure optimization have a significant positive impact on efficiency evaluation, but technological innovation and the urbanization level have a significant negative impact. Total factor productivity shows diminishing marginal utility based on the Malmquist index and its decomposition change. Restricted by the change in technological progress, the efficiency of digital villages in China in enabling urban-rural equilibrium needs to be further improved.


Assuntos
Agricultura , Urbanização , China , Eficiência , Humanos , Planejamento Social , Reforma Urbana
10.
Cereb Cortex ; 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35989311

RESUMO

Protein quality control (PQC) is essential for maintaining protein homeostasis and guarding the accuracy of neurodevelopment. Previously, we found that a conserved EBAX-type CRL regulates the protein quality of SAX-3/ROBO guidance receptors in Caenorhabditis elegans. Here, we report that ZSWIM8, the mammalian homolog of EBAX-1, is essential for developmental stability of mammalian brains. Conditional deletion of Zswim8 in the embryonic nervous system causes global cellular stress, partial perinatal lethality and defective migration of neural progenitor cells. CRISPR-mediated knockout of ZSWIM8 impairs spine formation and synaptogenesis in hippocampal neurons. Mechanistic studies reveal that ZSWIM8 controls protein quality of Disabled 1 (Dab1), a key signal molecule for brain development, thus protecting the signaling strength of Dab1. As a ubiquitin ligase enriched with intrinsically disordered regions (IDRs), ZSWIM8 specifically recognizes IDRs of Dab1 through a "disorder targets misorder" mechanism and eliminates misfolded Dab1 that cannot be properly phosphorylated. Adult survivors of ZSWIM8 CKO show permanent hippocampal abnormality and display severely impaired learning and memory behaviors. Altogether, our results demonstrate that ZSWIM8-mediated PQC is critical for the stability of mammalian brain development.

11.
Int J Mol Sci ; 23(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35955515

RESUMO

NF-YCs are important transcription factors with diverse functions in the plant kingdoms including seed development. NF-YC8, 9, 10, 11 and 12 are close homologs with similar seed-specific expression patterns. Despite the fact that some of the NF-YCs are functionally known; their biological roles have not been systematically explored yet, given the potential functional redundancy. In this study, we generated pentuple mutant pnfyc of NF-YC8-12 and revealed their functions in the regulation of grain quality and seed germination. pnfyc grains displayed significantly more chalkiness with abnormal starch granule packaging. pnfyc seed germination and post-germination growth are much slower than the wild-type NIP, largely owing to the GA-deficiency as exogenous GA was able to fully recover the germination phenotype. The RNA-seq experiment identified a total of 469 differentially expressed genes, and several GA-, ABA- and grain quality control-related genes might be transcriptionally regulated by the five NF-YCs, as revealed by qRT-PCR analysis. The results demonstrated the redundant functions of NF-YC8-12 in regulating GA pathways that underpin rice grain quality and seed germination, and shed a novel light on the functions of the seed-specific NF-YCs.


Assuntos
Giberelinas , Oryza , Ácido Abscísico/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Germinação/genética , Giberelinas/metabolismo , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/metabolismo
12.
Photodiagnosis Photodyn Ther ; 39: 102993, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35781093

RESUMO

INTRODUCTION: With the younger onset age of female lower genital tract diseases, there are increasing demands for protecting organ and tissue structures to preserve fertility and, therefore, effective fertility-sparing treatments that cause minimal normal tissue damage and less adverse reactions are urgently needed. OBJECTIVE: This study is aimed at reviewing information and achieving consensus on recommendations on the clinical applications of aminolevulinic acid-based photodynamic therapy (ALA-PDT) in female lower genital tract diseases. METHODS: Members of the expert panel held online and in-person meetings to discuss and revise drafts created by the steering committee based on the literature review and the clinical experiences of the expert panel. Opinions of the experts were transcribed and discussed in detail to ensure that the consensus statement best reflects the current advances in the field and the experts' view. RESULTS: After numerous rounds of meetings, experts unanimously agreed on the importance of ALA-PDT in the treatment of cervical squamous intraepithelial lesions (SIL), vaginal SIL, vulvar SIL, vulvar lichen sclerosus (VLS), and condyloma acuminatumon (CA). Experts also reached consensus on the recommended treatment regimen and treatment methods. CONCLUSION: This consensus aimed to provide practical basis and guidance for the clinical applications of ALA-PDT in female lower genital tract diseases in China. Of note, this is the only expert consensus prepared by board-certified specialists in gynecology and obstetrics in China. More evidence-based clinical studies should be made to update and expand the current recommendations.


Assuntos
Fotoquimioterapia , Neoplasias do Colo do Útero , Ácido Aminolevulínico/uso terapêutico , Feminino , Genitália , Humanos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Gravidez , Neoplasias do Colo do Útero/tratamento farmacológico
13.
ACS Nano ; 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35876466

RESUMO

Precise subcellular manipulation remains challenging in quantitative biological studies. After target modification and hierarchical assembly, nanoparticles can be functionalized for intracellular investigation. However, it remains unclear whether nanoparticles themselves can progressively manipulate subcellular processes, especially organellar networks. Mitochondria act as the energetic supply, whose fission dynamics are often modulated by molecular reagents. Here, using different-sized gold nanoparticles (AuNPs) as a model, we demonstrated the nanoparticle-driven controllable regulation on mitochondria. Compared with molecular reagents, AuNPs could induce size-dependent mitochondrial fission without detectable cell injury, and this process was reversible along with intracellular AuNPs' clearance. Mechanistically, it was attributed to the AuNPs-induced enhanced organelle interactome between lysosomes and mitochondria. Lysosomal accumulation of AuNPs induced lysosomal swelling and lysosomal motility alterations, promoting mitochondrial fission through the increased "kiss" events during the "kiss-and-run" moving of the lysosome-mitochondria interactome. This study highlights the fundamental understanding to fully explore the intrinsic capability of nanoparticles by engineering their basic properties. Also, it provides practical guidance to investigate the delicate nanolevel regulation on biological processes.

14.
Mol Ecol Resour ; 2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35844053

RESUMO

Schistosomiasis is a neglected tropical disease of humans caused by blood flukes of the genus Schistosoma, the only dioecious parasitic flatworm. Although aspects of sex determination, differentiation and reproduction have been studied in some Schistosoma species, almost nothing is known for Schistosoma japonicum, the causative agent of schistosomiasis japonica. This mainly reflects the lack of high-quality genomic and transcriptomic resources for this species. As current genomes for S. japonicum are highly fragmented, we assembled and report a chromosome-level reference genome (seven autosomes, the Z-chromosome and partial W-chromosome), achieving a substantially enhanced gene annotation. Utilizing this genome, we discovered that the sex chromosomes of S. japonicum and its congener S. mansoni independently suppressed recombination during evolution, forming five and two evolutionary strata, respectively. By exploring the W-chromosome and sex-specific transcriptomes, we identified 35 W-linked genes and 257 female-preferentially transcribed genes (FTGs) from our chromosomal assembly and uncovered a signature for sex determination and differentiation in S. japonicum. These FTGs clustering within autosomes or the Z-chromosome exhibit a highly dynamic transcription profile during the pairing of female and male schistosomula, thereby representing a critical phase for the maturation of the female worms and suggesting distinct layers of regulatory control of gene transcription at this development stage. Collectively, these data provide a valuable resource for further functional genomic characterization of S. japonicum, shed light on the evolution of sex chromosomes in this highly virulent human blood fluke, and provide a pathway to identify novel targets for development of intervention tools against schistosomiasis.

15.
Drug Des Devel Ther ; 16: 1697-1711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693534

RESUMO

Intestinal barrier injury and hyperglycemia are common in patients with sepsis. Bacteria translocation and systemic inflammatory response caused by intestinal barrier injury play a significant role in sepsis occurrence and deterioration, while hyperglycemia is linked to adverse outcomes in sepsis. Previous studies have shown that hyperglycemia is an independent risk factor for intestinal barrier injury. Concurrently, increasing evidence has indicated that some anti-hyperglycemic agents not only improve intestinal barrier function but are also beneficial in managing sepsis-induced organ dysfunction. Therefore, we assume that these agents can block or reduce the severity of sepsis by improving intestinal barrier function. Accordingly, we explicated the connection between sepsis, intestinal barrier, and hyperglycemia, overviewed the evidence on improving intestinal barrier function and alleviating sepsis-induced organ dysfunction by anti-hyperglycemic agents (eg, metformin, peroxisome proliferators activated receptor-γ agonists, berberine, and curcumin), and summarized some common characteristics of these agents to provide a new perspective in the adjuvant treatment of sepsis.


Assuntos
Hiperglicemia , Sepse , Humanos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Mucosa Intestinal , Insuficiência de Múltiplos Órgãos , Sepse/tratamento farmacológico
16.
Mol Immunol ; 149: 66-76, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35749835

RESUMO

Aminoglycoside antibiotic drugs induce hearing loss in children and adults every year; however, the pathological mechanisms remain unknown. Previous studies have shown that the accumulation of reactive oxygen species (ROS) and inflammation in the inner ear may be responsible for kanamycin (KM)-induced hair cell death and hearing loss. Nucleotide-binding oligomerization domain-, leucine-rich repeat-, and pyrin domain-containing protein 3 (NLRP3) is a specific ROS sensor that initiates inflammasome assembly as well as activates caspase-1 and downstream inflammatory factors. Therefore, this study aimed to determine whether NLRP3 inflammasomes are involved in KM-related hearing loss in mice. Compared with the control (saline) group, increased levels of activated caspase-1, interleukin (IL)-1ß, IL-18, N-terminal fragment of gasdermin D (GSDMD-N), and NLRP3 were detected by immunofluorescence, western blot, and enzyme-linked immunosorbent assay (ELISA) in the KM-plus-furosemide (LASIX)-treated group. Moreover, we also found that the NLRP3 inhibitor oridonin (Ori) could significantly rescue KM-related hearing loss by inhibiting NLRP3-inflammasome activation and caspase-1/GSDMD-related hair cell pyroptosis. These findings demonstrate that apoptosis, as well as pyroptosis, may be involved in KM-related hearing loss and that the NLRP3/caspase-1/GSDMD pathway may be a new target for treating aminoglycoside-induced hearing loss.


Assuntos
Perda Auditiva , Piroptose , Animais , Caspase 1/metabolismo , Diterpenos do Tipo Caurano , Cabelo/metabolismo , Perda Auditiva/induzido quimicamente , Perda Auditiva/tratamento farmacológico , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Canamicina , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo
17.
Sci Total Environ ; 839: 156281, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35644408

RESUMO

Amines in fine particles constitute a significant fraction of secondary organic aerosols and have adverse effects on air quality and human health. To understand the chemical composition, variation characteristics, and potential sources of fine particulate amines in the coastal area in northern China, field sampling and chemical analysis were conducted in coastal Qingdao in the winter of 2018 and 2019. A total of 15 major amines were identified and quantified by using an ultra-high-performance liquid chromatography coupled with mass spectrometry. The average concentration of total amines in PM2.5 samples was approximately 130 ng m-3. Dimethylamine was the most abundant species with average fractions of 44.8% and 65.0% in the quantified amines during the two field campaigns, followed by triethylamine (22.9% and 8.7%) and methylamine (8.3% and 4.4%). The amines in PM2.5 usually exhibited elevated concentrations in the presence of high levels of SO2 and NOx or in the condition of high relative humidity. A receptor model of positive matrix factorization was employed and seven major sources were identified, including coal combustion, industrial production, vehicle exhaust, biomass burning, agricultural activities, secondary formation, and marine emission. Surprisingly, most of 15 amines in fine particles primarily originated from the primary emissions of anthropogenic activities particularly related to coal combustion and industrial productions, which should be given close concern to address the amine pollution.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Aminas , China , Carvão Mineral/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Material Particulado/análise , Estações do Ano , Emissões de Veículos/análise
18.
Nat Commun ; 13(1): 3239, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688815

RESUMO

Many species with separate male and female individuals (termed 'gonochorism' in animals) have sex-linked genome regions. Here, we investigate evolutionary changes when genome regions become completely sex-linked, by analyses of multiple species of flatworms (Platyhelminthes; among which schistosomes recently evolved gonochorism from ancestral hermaphroditism), and roundworms (Nematoda) which have undergone independent translocations of different autosomes. Although neither the evolution of gonochorism nor translocations fusing ancestrally autosomal regions to sex chromosomes causes inevitable loss of recombination, we document that formerly recombining regions show genomic signatures of recombination suppression in both taxa, and become strongly genetically degenerated, with a loss of most genes. Comparisons with hermaphroditic flatworm transcriptomes show masculinisation and some defeminisation in schistosome gonad gene expression. We also find evidence that evolution of sex-linkage in nematodes is accompanied by transcriptional changes and dosage compensation. Our analyses also identify sex-linked genes that could assist future research aimed at controlling some of these important parasites.


Assuntos
Nematoides , Platelmintos , Animais , Compensação de Dosagem (Genética) , Evolução Molecular , Feminino , Masculino , Nematoides/genética , Platelmintos/genética , Cromossomos Sexuais/genética , Transcriptoma/genética
19.
JACS Au ; 2(5): 1032-1042, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35647602

RESUMO

Spin-center shift (SCS) is a radical process involving 1,2-radical translocation along with a two-electron ionic movement, such as elimination of an adjacent leaving group. Such a process was initially observed in some important biochemical transformations, and the unique property has also attracted considerable interest in synthetic chemistry. Experimental, kinetic, as well as computational studies have been performed, and a series of useful radical transformations have been developed and applied in organic synthesis based on SCS processes in the last 20 years. This Perspective is an overview of radical transformations involving the SCS mechanism.

20.
Sci Rep ; 12(1): 7096, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501426

RESUMO

Clays are known for their small particle sizes and complex layer stacking. We show here that the limited dimension of clay particles arises from the lack of long-range order in low-dimensional systems. Because of its weak interlayer interaction, a clay mineral can be treated as two separate low-dimensional systems: a 2D system for individual phyllosilicate layers and a quasi-1D system for layer stacking. The layer stacking or ordering in an interstratified clay can be described by a 1D Ising model while the limited extension of individual phyllosilicate layers can be related to a 2D Berezinskii-Kosterlitz-Thouless transition. This treatment allows for a systematic prediction of clay particle size distributions and layer stacking as controlled by the physical and chemical conditions for mineral growth and transformation. Clay minerals provide a useful model system for studying a transition from a 1D to 3D system in crystal growth and for a nanoscale structural manipulation of a general type of layered materials.

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