ABSTRACT
The outbreak of COVID-19 has exerted an enormous impact on society, enterprises, and individuals. It has affected the work attitudes and psychology of employees to a certain extent and their job stress (JS) has also augmented accordingly, leading to increased turnover intention (TI). With the survey responses of 720 employees of small and medium enterprises (SMEs) in China as the sample, we studied the impact of COVID-19 related JS and TI with the moderating effect of perceived organizational support (POS). We utilized linear and multiple regression analysis using Windows SPSS 25. The research findings indicated that the JS caused by COVID-19 in the first affected region (Hubei) was significantly stronger than that in other regions (non-Hubei). JS had a significant positive relationship with employees' TI, while POS had a significant negative connection with employees' TI. We also identified that POS weakened the positive association between JS and employees' TI. These findings are expected to be conducive to and conductive for the upcoming theoretical and empirical investigations as the founding guidelines, as well as for managers in formulating effective policies to curb JS, which would ultimately be helpful in reducing TI.
Subject(s)
COVID-19 , Occupational Stress , COVID-19/epidemiology , China/epidemiology , Cross-Sectional Studies , Humans , Intention , Occupational Stress/epidemiologyABSTRACT
Flos Carthami (FC), the dried flower of Carthamus tinctorius L., has widely been used for the treatment of cardiovascular diseases in China. A rapid fingerprint analysis method of FC was established by ultra-performance liquid chromatography (UPLC) for the quality control. The analysis time was shortened by 45 min, from 75 min on conventional high-performance liquid chromatography (HPLC) to 30 min on UPLC. Ten batches of FC samples from various sources were analyzed by the UPLC method. Coexisting peaks in FC chromatograms were chosen to calculate their relative retention time (RRT) and relative peak area (RPA). Thirteen characteristic peaks were illustrated on UPLC fingerprints. In the 24-h stability test, the relative standard deviation (RSD) for the RRT and RPA was <0.08% and 4.41%, respectively. The RSD for precision of the RRT and RPA was <0.05% and 4.26%, respectively. And the RSD for repeatability was <0.05% for the RRT and 3.91% for the RPA. The similarities of the 10 batches of FC were ranged from 0.938 to 0.995.Compared with the HPLC method, UPLC provided shorter analysis time, higher resolution and better separation performance, which is feasible for the quality control of FC.
ABSTRACT
In the title mol-ecule, C24H21NO2, the dihedral angle between the carbazole ring system [with a maximum deviation of 0.052â (2)â Å] and the benzene ring is 38.6â (1)°. In the crystal, weak bifurcated (C-H)2â¯O hydrogen bonds link the mol-ecules into chains along [100].
ABSTRACT
In the title mol-ecule, C21H20N2O2S, the dihedral angle between the mean plane of the carbazole ring system [maximum deviation = 0.021â (4)â Å] and the benzene ring is 80.15â (6)°. In the crystal, mol-ecules are linked by N-Hâ¯O and weak C-Hâ¯O hydrogen bonds into a C(8) chain along [001].
ABSTRACT
Sphenostylisins A-C (1-3), three complex dimeric compounds representing two novel carbon skeletons, along with an additional eight new compounds, sphenostylisins D-K (4-11), were isolated from the active chloroform-soluble extract of the root bark of Sphenostylis marginata ssp. erecta using a bioactivity-guided isolation approach. The structures were elucidated by means of detailed spectroscopic analysis, including NMR and HRESIMS analysis, and tandem MS fragmentation was utilized to further support the structures of 1-3. The absolute configuration of sphenostylisin C (3) was established by electronic circular dichroism analysis. Plausible biogenetic relationships between the modified isoflavonoids 1-11 are proposed, and a cyclization reaction of 9 was conducted to support one of the biogenetic proposals made. All of these pure isolates were evaluated against a panel of in vitro bioassays, and among the results obtained, sphenostylisin A (1) was found to be a very potent NF-κB inhibitor (IC50 = 6 nM).
Subject(s)
Isoflavones/chemistry , Isoflavones/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Sphenostylis/chemistry , Circular Dichroism , Magnetic Resonance Spectroscopy , Plant Extracts/isolation & purificationABSTRACT
Enantiopure tetra-ortho-substituted biphenyl phosphinoimine ligands (R(a),S)-3 and (S(a),S)-3 were synthesized via multistep reactions. The first asymmetric addition reactions of arylboronic acids to N-benzylisatin catalyzed by Pd(OAc)(2) and (R(a),S)-3 were studied to provide 3-aryl-3-hydroxyoxindoles in moderate yields and enantioselectivities.
Subject(s)
Biphenyl Compounds/chemical synthesis , Boronic Acids/chemistry , Isatin/analogs & derivatives , Isatin/chemistry , Palladium/chemistry , Biphenyl Compounds/chemistry , Catalysis , Ligands , Molecular Structure , StereoisomerismABSTRACT
Halenia elliptica D. Don, a popularly used ethnodrug from Qinghai-Tibetan plateau, was studied to reveal the indispensable morphoanatomic details. The fixed, sectioned, and stained plant materials as well as the epidermis, powder, and maceration materials were studied using light microscope according to the usual microscopic techniques. The results of the microscopic features were systematic described and illustrated. In the root, an endodermal cell was divided into 8-16-22 and 38-50-62 daughter cells in transverse section and in face view, respectively, and 9-11-13 phloem strands were present in primary structure; in the stem, stone cells were observed in the cortex, pericycle, and external phloem while 17-19-21 internal phloem strands were present in an incontinuous ring; in the pedicel, 8-10-12 internal phloem strands were observed to form an incontinuous ring; anisocytic and anomocytic stomata were present in leaf and sepal epidermis; pollen grain was with three germinal apertures and furrows; a few tracheids, a large number of spiral vessels, and various fibers were observed. Also, semiquantitative and quantitative micrographic parameter tables were simultaneously presented. Further, the key authentication parameters were concluded. The study indicated that light microscopy and related techniques could be unambiguously applied to the authentication of Halenia elliptica.
Subject(s)
Gentianaceae/anatomy & histology , Gentianaceae/cytology , Microscopy/methods , Plants, Medicinal/anatomy & histology , Plants, Medicinal/cytology , Flowers/anatomy & histology , Flowers/cytology , Plant Leaves/anatomy & histology , Plant Leaves/cytology , Plant Roots/anatomy & histology , Plant Roots/cytology , Plant Stems/anatomy & histology , Plant Stems/cytology , TibetABSTRACT
A novel class of sulfinamido alcohol ligands 1-6 was synthesized from (S)-tert-butanesulfinamide. These ligands showed excellent catalytic activities and enantiomeric selectivities in asymmetric additions of diethylzinc to aromatic aldehydes.