We explored whether medical health workers had more psychosocial problems than nonmedical health workers during the COVID-19 outbreak.
An online survey was run from February 19 to March 6, 2020; a ...total of 2,182 Chinese subjects participated. Mental health variables were assessed via the Insomnia Severity Index (ISI), the Symptom Check List-revised (SCL-90-R), and the Patient Health Questionnaire-4 (PHQ-4), which included a 2-item anxiety scale and a 2-item depression scale (PHQ-2).
Compared with nonmedical health workers (n = 1,255), medical health workers (n = 927) had a higher prevalence of insomnia (38.4 vs. 30.5%, p < 0.01), anxiety (13.0 vs. 8.5%, p < 0.01), depression (12.2 vs. 9.5%; p< 0.04), somatization (1.6 vs. 0.4%; p < 0.01), and obsessive-compulsive symptoms (5.3 vs. 2.2%; p < 0.01). They also had higher total scores of ISI, GAD-2, PHQ-2, and SCL-90-R obsessive-compulsive symptoms (p ≤ 0.01). Among medical health workers, having organic disease was an independent factor for insomnia, anxiety, depression, somatization, and obsessive-compulsive symptoms (p < 0.05 or 0.01). Living in rural areas, being female, and being at risk of contact with COVID-19 patients were the most common risk factors for insomnia, anxiety, obsessive-compulsive symptoms, and depression (p < 0.01 or 0.05). Among nonmedical health workers, having organic disease was a risk factor for insomnia, depression, and obsessive-compulsive symptoms (p < 0.01 or 0.05).
During the COVID-19 outbreak, medical health workers had psychosocial problems and risk factors for developing them. They were in need of attention and recovery programs.
Regulating both the chemo‐ and diastereoselectivity, divergently, of a reaction is highly attractive but extremely challenging. Presented herein is a catalyst‐controlled switch in the chemo‐ and ...diastereodivergent annulation reactions of Morita–Baylis–Hillman carbonates, derived from isatins and 2‐alkylidene‐1H‐indene‐1,3(2H)‐diones, in exclusive α‐regioselectivity. α‐Isocupreine efficiently catalyzed 2+1 reactions to access cyclopropane derivatives, and the diastereodivergent 3+2 annulations were accomplished by employing either a chiral phosphine or a DMAP‐type molecule. All reactions exhibited excellent chemoselectivities, and good to remarkable stereoselectivities were furnished, thus leading to a collection of compounds with skeletal and stereogenic diversity. Moreover, DFT computational calculations elucidated the catalyst‐based switch in mechanism.
Switching it up: The title reactions have been accomplished by employing different chiral Lewis base catalysts, thus resulting in a broad collection of chiral compounds with high structural and stereochemical diversity (see scheme). DFT calculations indicate that the structure of Lewis base plays a key role in controlling the chemo‐ and diastereoselectivity. Boc=tert‐butoxycarbonyl.
Friend leukemia virus integration 1 (FLI1), an ETS transcription factor family member, acts as an oncogenic driver in hematological malignancies and promotes tumor growth in solid tumors. However, ...little is known about the mechanisms underlying the activation of this proto-oncogene in tumors.
Immunohistochemical staining showed that FLI1 is aberrantly overexpressed in advanced stage and metastatic breast cancers. Using a CRISPR Cas9-guided immunoprecipitation assay, we identify a circular RNA in the FLI1 promoter chromatin complex, consisting of FLI1 exons 4-2-3, referred to as FECR1.Overexpression of FECR1 enhances invasiveness of MDA-MB231 breast cancer cells. Notably, FECR1 utilizes a positive feedback mechanism to activate FLI1 by inducing DNA hypomethylation in CpG islands of the promoter. FECR1 binds to the FLI1 promoter in cis and recruits TET1, a demethylase that is actively involved in DNA demethylation. FECR1 also binds to and downregulates in trans DNMT1, a methyltransferase that is essential for the maintenance of DNA methylation.
These data suggest that FECR1 circular RNA acts as an upstream regulator to control breast cancer tumor growth by coordinating the regulation of DNA methylating and demethylating enzymes. Thus, FLI1 drives tumor metastasis not only through the canonical oncoprotein pathway, but also by using epigenetic mechanisms mediated by its exonic circular RNA.
As promising cathode for sodium‐ion batteries, Na+ Superionic Conductor (NASICON)‐type materials have attracted attention owing to their excellent structural stability, superior ionic conductivity, ...and small volume expansion. However, the vanadium‐based NASICON‐type cathode with the biotoxicity and exorbitant price of V element and the iron‐based cathode with low mean working voltage as well as the intrinsic poor electronic conductivity of polyanionic compounds hinder their practical applications. Herein, a double‐carbon‐layer decorated heterogeneous composite, Na3V2(PO4)3‐Na3Fe2(PO4)(P2O7) (NVFPP/C/G), is successfully prepared for addressing these limitations. Due to their synergistic effect, NVFPP/C/G exhibits excellent electrochemical performance in half‐cell system and superior full‐cell performance when matched with hard carbon anode. Furthermore, the phase composition, electrode kinetics, and phase transition are confirmed by combined analyses of slow scanning power X‐ray diffraction, high‐resolution transmission electron microscopy, cyclic voltammetry with various scan rates, galvanostatic intermittent titration technique, ex situ X‐ray photoelectron spectra, and in situ X‐ray diffraction. This study portends a promising strategy to utilize composite structure engineering for developing advanced polyanionic cathodes.
A double‐carbon‐layer decorated heterogeneous Na3V2(PO4)3‐Na3Fe2(PO4)(P2O7) composite is proposed as cathode for sodium‐ion batteries. Due to the synergistic effect, it exhibits excellent electrochemical performance in half‐cell system and superior full‐cell performance. The heterogeneous composite structure engineering strategy provides a new approach to design high‐performance polyanionic cathodes for batteries.
Multiplexed tissue imaging enables precise, spatially resolved enumeration and characterization of cell types and states in human resection specimens. A growing number of methods applicable to ...formalin-fixed, paraffin-embedded (FFPE) tissue sections have been described, the majority of which rely on antibodies for antigen detection and mapping. This protocol provides step-by-step procedures for confirming the selectivity and specificity of antibodies used in fluorescence-based tissue imaging and for the construction and validation of antibody panels. Although the protocol is implemented using tissue-based cyclic immunofluorescence (t-CyCIF) as an imaging platform, these antibody-testing methods are broadly applicable. We demonstrate assembly of a 16-antibody panel for enumerating and localizing T cells and B cells, macrophages, and cells expressing immune checkpoint regulators. The protocol is accessible to individuals with experience in microscopy and immunofluorescence; some experience in computation is required for data analysis. A typical 30-antibody dataset for 20 FFPE slides can be generated within 2 weeks.
Antiferroelectric‐based dielectric capacitors are receiving tremendous attention for their outstanding energy‐storage performance and extraordinary flexibility in collecting pulsed powers. ...Nevertheless, the in situ atomic‐scale structural‐evolution pathway, inherently coupling to the energy storage process, has not been elucidated for the ultimate mechanistic understanding so far. Here, time‐ and atomic‐resolution structural phase evolution in antiferroelectric PbZrO3 during storage of energy from the electron‐beam illumination is reported. By employing state‐of‐the‐art negative‐spherical‐aberration imaging technique, the quantitative transmission electron microscopy study presented herein clarifies that the hierarchical evolution of polar oxygen octahedra associated with the unit‐cell volume change and polarization rotation accounts for the stepwise antiferroelectric‐to‐ferroelectric phase transition. In particular, an unconventional ferroelectric category—the ferrodistortive phase characteristic of a unique cycloidal polarization order—is established during the dynamic structure investigation. Through clarifying the atomic‐scale phase transformation pathway, findings of this work unveil a new territory to explore novel ferrodistortive phases in energy‐storage materials with the nonpolar‐to‐polar phase transitions.
Antiferroelectrics are an important material system for electrostatic energy storage. However, the associated antiferroelectric–ferroelectric transition has not been clarified in the past decades. Driven by electron‐beam irradiation, time‐ and atomic‐resolution electron microscopy unveils a novel ferrodistortive phase, characteristic of a cycloidal polarization order, during the phase‐transition process. This opens up a field to search for ferroelectrics with noncollinear polarization orders.
A phosphorus allotrope that has not been observed so far, ring‐shaped phosphorus consisting of alternate P8 and P2 structural units, has been assembled inside multi‐walled carbon nanotube ...nanoreactors with inner diameters of 5–8 nm by a chemical vapor transport and reaction of red phosphorus at 500 °C. The ring‐shaped nanostructures with surrounding graphene walls are stable under ambient conditions. The nanostructures were characterized by high‐resolution transmission electron microscopy, scanning transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, Raman scattering, attenuated total reflectance Fourier transform infrared spectroscopy, and X‐ray photoelectron spectroscopy.
Ring‐shaped phosphorus: A new phosphorus allotrope, ring‐shaped phosphorus, has been synthesized within nanoreactors of carbon nanotubes by a vapor‐phase reaction. The self‐assembled ring‐shaped phosphorus nanostructures, consisting of sequential P8 and P2 structural units, within carbon nanotubes (inside diameter 5–8 nm) are stable under ambient conditions.
Resistive switching based on transition metal oxide memristive devices is suspected to be caused by the electric‐field‐driven motion and internal redistribution of oxygen vacancies. Deriving the ...detailed mechanistic picture of the switching process is complicated, however, by the frequently observed influence of the surrounding atmosphere. Specifically, the presence or absence of water vapor in the atmosphere has a strong impact on the switching properties, but the redox reactions between water and the active layer have yet to be clarified. To investigate the role of oxygen and water species during resistive switching in greater detail, isotope labeling experiments in a N2/H218O tracer gas atmosphere combined with time‐of‐flight secondary‐ion mass spectrometry are used. It is explicitly demonstrated that during the RESET operation in resistive switching SrTiO3‐based memristive devices, oxygen is incorporated directly from water molecules or oxygen molecules into the active layer. In humid atmospheres, the reaction pathway via water molecules predominates. These findings clearly resolve the role of humidity as both oxidizing agent and source of protonic defects during the RESET operation.
The interaction of memristive devices with the atmosphere through operation in a N2/H218O tracer gas atmosphere combined with time‐of‐flight secondary‐ion mass spectrometry is reported in detail. Based on this experimental approach, the role of oxygen species in the atmosphere is clarified, and it is shown that the reaction with atmospheric species is an essential part of the switching mechanism.
Redox-based resistive switching phenomena are found in many metal oxides and hold great promise for applications in next-generation memories and neuromorphic computing systems. Resistive switching ...involves the formation and disruption of electrically conducting filaments through ion migration accompanied by local electrochemical redox reactions. These structural changes are often explained by point defects, but so far clear experimental evidence of such defects is missing. Here, nanosized conducting filaments in Fe-doped SrTiO3 thin-film memories are visualized, for the first time, by scanning transmission electron microscopy and core-loss spectroscopy. Conducting filaments are identified by a high local concentration of trivalent titanium ions correlating to oxygen vacancies. Strontium vacancies and lattice distortions also exist in the filaments. Despite a high concentration of defects in the filaments, their general SrTiO3 perovskite structure is essentially preserved. First insights into the switching mechanism are deduced from a snapshot simultaneously showing multiple nanosized filaments in different evolutionary stages. The coexistence of a high Ti3+ concentration along with Sr- and O-vacancies in the conducting filaments provides atomic scale explanations for the resistive switching mechanisms. The results shed unique light on the complexity of the conducting filament formation that cation and anion defects need to be considered jointly.
Recently, extended mixed dislocations were observed at a 001/(100) low-angle tilt grain boundary of a SrTiO
3
bicrystal because of a slight twist between the two crystal parts. The
b
=
a
201/(100) ...mixed dislocations at the grain boundary dissociate into three dislocations with Burgers vector
b
of
a
/2101,
a
100, and
a
/2101, respectively. A structure model has been proposed in particular for the dislocation cores of the two partials with
b
=
a
/2101 based on the high-angle annular dark-field (HAADF) images acquired by scanning transmission electron microscopy (STEM). However, the details of the atomic structure and the chemical composition of the dislocation cores remain unexplored, especially for the
b
=
a
100 dislocation that is evidently disassociated into two
b
=
a
/2101 partial dislocations. In this work, we study the further atomic details of the extended mixed dislocations, in particular the local chemistry, in a SrTiO
3
bicrystal using STEM, electron energy loss spectroscopy (EELS), and energy dispersive X-ray (EDX) spectroscopy techniques. By these atomic-scale imaging techniques, we reveal a unique feature for the atomic structure of the
b
=
a
201/(100) extended mixed dislocation, which we named as local crystallographic shear (LCS) structures. In addition, we identify a rock salt FCC-type TiO
x
(
x
= 0.66-1.24) phase at the locations of the extended mixed dislocations. In contrast to the insulating TiO
2
phases, the TiO
x
phase is known to exhibit very low electrical resistivity of only several μΩ cm. In this regard, the extended mixed dislocations of SrTiO
3
comprising the FCC TiO
x
phase may function as the conducting filament in resistive switching processes by completion and disruption of the TiO
x
phase along the dislocation cores through electrically stimulated redox reactions.
Atomic details of extended mixed dislocations in a SrTiO
3
bicrystal are studied using scanning transmission electron microscopy, electron energy loss spectroscopy, and energy dispersive X-ray spectroscopy techniques.
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