Massive multiple-input multiple-output (M-MIMO) technology is considered to be a key enabling technology for future wireless communication systems. One of the challenges in effectively implementing ...an advanced precoding scheme to a large-scale array antenna is how to reduce the mutual coupling among antenna elements. In this paper, a new concept that is called array-antenna decoupling surface (ADS) for reducing the mutual coupling between antenna elements in a large-scale array antenna is proposed for the first time. An ADS is a thin surface that is composed of a plurality of electrical small metal patches and is placed in front of the array antenna. The partially diffracted waves from the ADS can be controlled to cancel the unwanted coupled waves. Two practical design examples are given to illustrate the design process and considerations, and to demonstrate the usefulness of ADS for the applications of phased array antennas and M-MIMO systems when commonly used precoding schemes are applied. The attractive features of ADS include its applicability to a large-scale array antenna; suitability for a wide range of antenna forms; wide decoupling bandwidth; and simplicity in implementation.
The development of kesterite Cu2ZnSn(S,Se)4 thin‐film solar cells is currently hindered by the large deficit of open‐circuit voltage (Voc), which results from the easy formation of CuZn antisite ...acceptor defects. Suppressing the formation of CuZn defects, especially near the absorber/buffer interface, is thus critical for the further improvement of kesterite solar cells. In this paper, it is shown that there is a large disparity between the defects in Cu‐ and Ag‐based kesterite semiconductors, i.e., the CuZn or CuCd acceptor defects have high concentration and are the dominant defects in Cu2ZnSn(S,Se)4 or Cu2CdSnS4, but the AgZn acceptor has only a low concentration and the dominant defects are donors in Ag2ZnSnS4. Therefore, the Cu‐based kesterites always show p‐type conductivity, while the Ag‐based kesterites show either intrinsic or weak n‐type conductivity. Based on this defect disparity and calculated band alignment, it is proposed that the Voc limit of the kesterite solar cells can be overcome by alloying Cu2ZnSn(S,Se)4 with Ag2ZnSn(S,Se)4, and the composition‐graded (Cu,Ag)2ZnSn(S,Se)4 alloys should be ideal light‐absorber materials for achieving higher efficiency kesterite solar cells.
A new strategy is proposed to overcome the Voc bottleneck and increase the efficiency of the kesterite solar cells. This is achieved by forming composition‐graded (Cu1–xAgx)2ZnSn(S,Se)4 alloys as the absorber layer.
Aims
The objective of this study is to explore the various latent categories within the sleep quality of night shift nurses and to investigate whether shift‐related factors predispose nurses to ...higher levels of occupational stress and anxiety.
Design
This is a cross‐sectional study.
Methods
From November to December 2020, registered nurses from 18 tertiary hospitals and 16 secondary hospitals in Chongqing were selected through convenience sampling for this study. Latent class analysis was used to investigate the sleep quality of nurses working night shifts. Furthermore, univariate analysis and logistic multivariate analysis were utilized to identify the contributing factors to occupational stress and anxiety.
Results
The four latent categories of Pittsburgh Sleep Quality Index for night shift nurses were identified as ‘Low Sleep Disorder Group’ (56.34%), ‘Moderate Sleep Disorder Group’ (37.27%), ‘High Sleep Disorder Non‐Reliant on Sleeping medication Group’ (4.89%) and ‘High Sleep Disorder Reliant on Sleeping medication Group’ (1.50%). The results showed that having a night‐shift frequency of 3–4 times per month, night‐shift durations of 9–12 h, sleep time delay after night shift (≥2 h), total sleep time after night shift less than 4 h were shift‐related factors that increased the levels of occupational stress and anxiety.
Conclusion
The sleep quality of night shift nurses demonstrates heterogeneity and can be classified into four latent categories. Higher frequency of night shifts, extended work hours and insufficient rest time are all associated with increased levels of occupational stress and anxiety.
Impact
By identifying the four latent categories of sleep quality among night shift nurses, this study sheds light on the relationship between sleep patterns and levels of occupational stress and anxiety. These findings have important implications for healthcare institutions in the management of nurse well‐being and work schedules.
Patient or Public Contribution
No patient or public contribution.
In this communication, a dual-band dual-polarized antenna with very small frequency spacing is proposed for base station applications. The antenna includes one lower band (LB) and one upper band (UP) ...dual-polarized filtering dipole elements. The lower band antenna is embedded in the upper band antenna. Guided by the well-known coupling matrix model, each antenna design yields third-order filter responses with two radiation nulls at the same stopband. The filtering performance is realized by using radiating structures to reduce the insertion loss. In addition to introducing the first radiation null with a parasitic element (PE), a filtering parasitic arm (PA) is adopted to further improve the selectivity and bandwidth of the antennas. As a result, the two adjacent working bands can be very closely placed with high out-of-band suppression. To validate the idea, a dual-band dual-polarized antenna is designed and fabricated, operating at 1.7-2.17 GHz and 2.3-2.7 GHz with isolation of more than 20 dB without any filtering in feeding circuits. The measured results agree well with the simulations, verifying that the proposed antenna is suitable for ever-challenging wireless communication applications.
In recent years, sports events have continuously attracted people’s attention, and people’s enthusiasm and participation in sports have been rising. The sports + tourism model can meet people’s ...travel needs and enjoy sports-related entertainment and experiences. With the expansion of sports tourism, people have a new understanding of sports + tourism. Sports tourism based on the current strategic background of national fitness is an emerging industry, and it has had a certain degree of development prospects before this. This article explores traditional sports tourism with national characteristics under the blessing of the wireless sensor network. This exploration discusses and explores the development and construction of local sports + tourism in terms of literature and logical analysis. The experimental results of this article show that most consumers are not satisfied with the construction of sports tourism network information, and they are the least satisfied with key information coverage, e-commerce, and security systems. It shows that in these aspects, the construction of sports tourism informatization is relatively lagging, and it is in urgent need of improvement and improvement.
A highly efficient majority‐rules effect of poly(quinoxaline‐2,3‐diyl)s (PQXs) bearing 2‐butoxymethyl chiral side chains at the 6‐ and 7‐positions was established and attributed to large ΔGh values ...(0.22–0.41 kJ mol−1), which are defined as the energy difference between P‐ and M‐helical conformations per chiral unit. A PQX copolymer prepared from a monomer derived from (R)‐2‐octanol (23 % ee) and a monomer bearing a PPh2 group adopted a single‐handed helical structure (>99 %) and could be used as a highly enantioselective chiral ligand in palladium‐catalyzed asymmetric reactions (products formed with up to 94 % ee), in which the enantioselectivity could be switched by solvent‐dependent inversion of the helical PQX backbone.
Bowing to the majority: Poly(quinoxaline‐2,3‐diyl) containing PPh2 groups and chiral side chains derived from (R)‐2‐octanol with 23 % ee exhibited a single‐handed‐helical conformation and served as a highly enantioselective chiral ligand in palladium‐catalyzed reactions (see scheme; se=screw‐sense excess). The chirality of the polymer could be switched by a solvent effect to enable the synthesis of the enantiomeric products.
Plant-pathogen interactions induce a signal transmission series that stimulates the plant's host defense system against pathogens and this, in turn, leads to disease resistance responses. Plant ...innate immunity mainly includes two lines of the defense system, called pathogen-associated molecular pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). There is extensive signal exchange and recognition in the process of triggering the plant immune signaling network. Plant messenger signaling molecules, such as calcium ions, reactive oxygen species, and nitric oxide, and plant hormone signaling molecules, such as salicylic acid, jasmonic acid, and ethylene, play key roles in inducing plant defense responses. In addition, heterotrimeric G proteins, the mitogen-activated protein kinase cascade, and non-coding RNAs (ncRNAs) play important roles in regulating disease resistance and the defense signal transduction network. This paper summarizes the status and progress in plant disease resistance and disease resistance signal transduction pathway research in recent years; discusses the complexities of, and interactions among, defense signal pathways; and forecasts future research prospects to provide new ideas for the prevention and control of plant diseases.
Mitochondria form a dynamic network that responds to physiological signals and metabolic stresses by altering the balance between fusion and fission. Mitochondrial fusion is orchestrated by conserved ...GTPases MFN1/2 and OPA1, a process coordinated in yeast by Ugo1, a mitochondrial metabolite carrier family protein. We uncovered a homozygous missense mutation in SLC25A46, the mammalian orthologue of Ugo1, in a subject with Leigh syndrome. SLC25A46 is an integral outer membrane protein that interacts with MFN2, OPA1, and the mitochondrial contact site and cristae organizing system (MICOS) complex. The subject mutation destabilizes the protein, leading to mitochondrial hyperfusion, alterations in endoplasmic reticulum (ER) morphology, impaired cellular respiration, and premature cellular senescence. The MICOS complex is disrupted in subject fibroblasts, resulting in strikingly abnormal mitochondrial architecture, with markedly shortened cristae. SLC25A46 also interacts with the ER membrane protein complex EMC, and phospholipid composition is altered in subject mitochondria. These results show that SLC25A46 plays a role in a mitochondrial/ER pathway that facilitates lipid transfer, and link altered mitochondrial dynamics to early‐onset neurodegenerative disease and cell fate decisions.
Synopsis
Whole‐exome sequencing in a Leigh syndrome patient identified mutations in SLC25A46, a degenerate member of the mitochondrial metabolite transport family, linking altered mitochondrial dynamics to early‐onset neurodegenerative disease.
Loss of SLC25A46 results in mitochondrial hyperfusion and striking changes in mitochondrial architecture.
SLC25A46 is an outer membrane protein that interacts with MFN2, OPA1, the MICOS complex, and the EMC complex in the ER.
Loss of SLC25A46 results in altered ER morphology and marked changes in the phospholipid composition of the mitochondrial membranes.
Loss of SLC25A46 results in premature cellular senescence in dividing cells.
Whole‐exome sequencing in a Leigh syndrome patient identified mutations in SLC25A46, a degenerate member of the mitochondrial metabolite transport family, linking altered mitochondrial dynamics to early‐onset neurodegenerative disease.
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