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Indoor organic photovoltaic provides a promising energy for the off-grid self-power supply technology of the Internet of Things industry. In this work, the indoor organic photovoltaic devices were prepared with wide bandgap polymer PM6 as donor and fullerene derivatives PC71BM as acceptor. The photovoltaic performances, the carrier recombination characteristics, and the molecular packing of the PM6:PC71BM device were studied in detail as compared with the photovoltaic device with non-fullerene acceptor Y6. The matched spectral response range with indoor lighting source and rational energy level alignment of PC71BM suppresses carrier recombination under slim light illumination, improving the open-circuit voltage and fill factor of the prepared fullerene device, and an enhanced power conversion efficiency (PCE) of 18.7% is achieved under white LED illumination with intensity of 1000 Lux, while the PCE of the photovoltaic device with Y6 acceptor is only 14.7%. The superior photovoltaic performance of PM6:PC71BM organic photovoltaic device indicates that fullerene acceptors are effective materials choice for preparing high-performance organic photovoltaic devices under slim light illumination, and fullerene derivatives would play an important role in the preparation of high-efficiency indoor photovoltaic devices for Internet of Things utilization. [ABSTRACT FROM AUTHOR]

Up-conversion fluorescent materials serve a significant function as the detection materials of temperature sensors. In this study, a series of green-emitting LiLuW 2 O 8 :Yb3+, Er3+ phosphors applied in optical temperature sensing detection were successfully synthesized via the solid-state process in air. The crystal structure, luminescence properties, luminescence mechanism, and optical temperature sensing properties of samples were investigated. LiLuW 2 O 8 :Yb3+, Er3+ phosphor with excitation at 980 nm emits pronounced green emissions owing to the 2H 11/2 → 4I 15/2 and 4S 3/2 → 4I 15/2 transitions of Er3+ ions. The whole emission processes of LiLu 0.72 W 2 O 8 :0.24 Yb3+, 0.04Er3+ sample are all two-photon processes. Moreover, we apply thermal coupling levels (2H 11/2 , 4S 3/2) for temperature sensing and the value of sensing sensitivity can reach the maximum of about 1.41% K−1. All the experimental results imply that LiLuW 2 O 8 :Yb3+, Er3+ phosphors show good potential in temperature sensing. • Novel LiLuW 2 O 8 :Yb3+, Er3+ phosphors were successfully prepared for the first time. • The crystal structure and photoluminescence properties were investigated in detail. • The LiLuW 2 O 8 :Yb3+, Er3+ phosphors show high sensitivity for temperature sensing, and the S r was found to be as high as 1.41% K−1. • The present phosphors could have potential application in optical temperature sensors. [ABSTRACT FROM AUTHOR]

Recently, Mn4+-doped phosphors have attracted widespread attention in the field of indoor plant growth lighting on account of their strong far-red emitting properties. As a new type of dual-activator sensing system to further enhance the accuracy of temperature measurement, Mn4+ and Eu3+ ion co-doped double perovskite phosphors can simultaneously meet high temperature relative sensitivity and excellent signal discrimination ability for optical temperature sensing. In this work, a series of Sr 2 ScTaO 6 phosphors singly doped with Mn4+, and co-doped with Mn4+/Eu3+ were synthesized. And the Mn4+-doping causes the spectra of the as-prepared phosphors to partially overlap with the absorption spectrum of plant pigments (P R and P FR), which demonstrated that the as-synthetized phosphors can be well used as a potential artificial light source for the field of indoor plant growth. Furthermore, we particularly make a thorough inquiry into the temperature sensing performance of the as-obtained Sr 2 ScTaO 6 :Mn4+, Eu3+ phosphors at 300 K–500 K, and the maximum relative sensitivity can reach 3.66% K−1. The above unique characteristics can prove that the as-obtained phosphors have the great potentiality to be used for indoor plant growth lighting and optical temperature sensing. • The Sr 2 ScTaO 6 :Mn4+, Eu3+ phosphors were synthesized for the first time. • The Rietveld refinement of the corresponding samples was tested to further analyze the doped structure. • The Vienna Ab-initio Simulation Package (VASP) module is used for calculating the electronic structure of Sr 2 ScTaO 6 host based on the DFT method. • The maximum relative sensitivity of Sr 2 ScTaO 6 :Mn4+,Eu3+ reaches 3.66% K−1. • The unique characteristics of the Sr 2 ScTaO 6 :Mn4+, Eu3+ phosphor might provide a lot of possible application including plant growth lighting and optical temperature sensing. [ABSTRACT FROM AUTHOR]

Feline upper respiratory tract disease (URTD) is a common but complicated disease that occurs in domestic cats, worldwide. 396 cats in Guangxi Province, China were screened for URTD-associated pathogens from March 2022 to August 2023. Mycoplasma felis was found to be the most prevalent infectious agent with a positivity rate of 24.75 %, followed by feline calicivirus (FCV), Chlamydia felis , feline herpesvirus 1 (FHV-1) and feline influenza A virus (FeIAV) with rates of 15.91, 11.62, 5.56 and 1.52 %, respectively. In particular, C. felis and M. felis were found in 13 of 55 co-infected cats. Of the 46 C. felis -positive samples, one strain, named as GXNN36, was successfully isolated using chicken embryos and it was characterized both in vivo and in vitro. For the cat studies, both high- and low-dose challenged groups showed severe conjunctivitis, accompanied by transient fever and respiratory symptoms. C. felis replicated well in turbinate, trachea and lung tissues with high copy numbers and the infection subsequently spread to the livers, spleens, pancreas, kidneys, hearts and intestines. These findings will help our understanding of the role of C. felis in feline URTD and provide a valuable model to evaluate the efficacy of vaccines and therapeutic remedies in the future. • Chlamydia felis plays an important role in feline URTD, co-infecting with Mycoplasma felis. • The isolation and identification of Chlamydia felis was systemically described. • The pathogenesis was evaluated in cat study, which provided a valuable model to develop the vaccine and medicine. [ABSTRACT FROM AUTHOR]

A novel series of Er3+ doped LiYbW 2 O 8 phosphors were synthesized by high-temperature solid-state process. Upon 980 nm NIR laser excitation, the up-conversion emission spectra show that the intense green emissions and weak red emissions can be proposed as the transitions of 2H 11/2 →4I 15/2 , 4S 3/2 →4I 15/2 , 4F 9/2(2) →4I 15/2 and 4F 9/2(1) →4I 15/2 of Er3+ ions, respectively. The optical temperature sensing properties were carefully investigated on the basis of fluorescence intensity ratio (FIR) technology about energy level transitions of 2H 11/2 →4I 15/2 and 4S 3/2 →4I 15/2 in the range from 300 K to 500 K. Moreover, the maximum values of relative sensitivity (S r) and absolute sensitivity (S a) are separately about 1.62% K−1 at 300 K and 0.64% K−1 at 500 K, which can prove that the sensitivity of LiYbW 2 O 8 :Er3+ is superior to the latest reported materials for temperature sensors. Results evidence that the Er3+ doped LiYbW 2 O 8 phosphors can be outstanding candidates for optical temperature sensors with high S r and S a. [ABSTRACT FROM AUTHOR]

Low-dimensional organic-inorganic hybrid metal halides (OIMHs) have become an emerging class of light-emitting materials. Two zero-dimensional (0D) lead-free organic (EnrofloH 2) 4 Mn 3 X 12 (X = Cl, Br) has been reported in this work. Upon 338 and 340 nm excitation, (EnrofloH 2) 4 Mn 3 Cl 12 ·2Cl and (EnrofloH 2) 4 Mn 3 Br 12 ·2Br exhibit emission peaking at 460, 514 nm and 460, 520 nm respectively. It was noticed that the choice of the halide could profoundly govern the luminescent subjects (ENR or Mn2+) through the altered energy transfer. Different halogens could influence the rigidity of ENR organic cations by changing their stacking patterns and band gaps, thus manipulating their luminescent properties. The bandgap behaviors have been revealed by density functional theory calculations. Based on the results, the emission of both compounds come from organic cations (EnrofloH 2 2+) and 4D-6A 1 transition of Mn2+ ions. The spectral interplay of these emission bands is governed by the temperature and the possibility of exchanging mechanisms between two emission centers. • Novel two zero-dimensional organic−inorganic hybrid metal halides of (EnrofloH 2) 4 Mn 3 X 12 were successfully prepared. • The crystal structure and photoluminescence properties were investigated in detail. • It presents an interesting study into tuning luminescence properties by using different halides. [ABSTRACT FROM AUTHOR]

The reassortment between avian H9N2 and Eurasian avian-like (EA) H1N1 viruses may have potentially changed from avian-to-mammals adaptation. This study generated 20 reassortant viruses with the introduction of H1N1/2009 internal genes from EA H1N1 virus into H9N2 virus. 12 of these recovered the replication capability both in the lungs and turbinate samples. 10 of 12 obtained PA gene segments from the ribonucleoprotein (RNP) complexes of the EA H1N1 virus, and 3 exhibited extreme virulence. Specially, the combination of PB2, PA and NP genes could overcome the species-specific restriction in human cells. Analysis of the polymerase activities found that introduction of the PA gene resulted in increased polymerase activity. These findings indicated that RNP complexes from EA H1N1 virus could confer an adaptation advantage and high compatibility to avian H9N2 virus. This raises new concerns for public health due to the possible coexistence of H9N2 and EA H1N1 viruses in dogs. • PA gene from H1N1/2009 lineage of EA H1N1 virus is critical for enhanced polymerase activity and viral replication. • The introduction of PB2 gene in the combination of PA and NP genes helps evade restriction in human cells and results in significantly increased pathogenicity in mice. • The combination of PB2, PA and NP genes from H1N1/2009 lineage of EA H1N1 virus is optimal to confer a cross-species adaptation advantage. [ABSTRACT FROM AUTHOR]

A series of CaLa 1- x LiTeO 6 : x Dy3+ phosphors were synthesized via a conventional solid-state reaction method, and the effects of different Dy3+ doping concentrations on the luminescence properties of the phosphors were studied. The excitation spectrum indicated that these synthesized phosphors had strong absorption bands in near-ultraviolet (n-UV) region in the range from 300 to 500 nm. There were two sharp emission peaks in the visible region, which were located at 483 nm, 574 nm, corresponding to transitions of 4F 9/2 →6H 15/2 (magnetic dipole transition) and 4F 9/2 →6H 13/2 (electric dipole transition), respectively. The phosphor CaLa 0.95 LiTeO 6 :0.05Dy3+ shows superior thermal stability. When the temperature rises to 425 K, the luminous intensity remains at 79% compared with the initial intensity of 300 K. These results demonstrate that the CaLa 1- x LiTeO 6 : x Dy3+ phosphors have great potential as a single-phase luminescence material for near-ultraviolet (n-UV) excitation. [ABSTRACT FROM AUTHOR]

• An apple tree yield prediction model was developed by using ensemble learning. • The contribution of spectral and structural features to orchard yield was discussed. • An automatic channel was developed to extract growth characteristics. As one of the world's most popular fruit, apple tree yield prediction before harvest plays an important role in optimizing orchard nutrition management, especially at the individual tree level. However, few studies focus on fruit-tree yield prediction with remote-sensing technology whereas most of them aim at field crops. Current fruits identifying and counting methods often fail to produce the expected result due to light and occlusion in complex orchard conditions. Since both the spectral and morphological characteristics of tree canopy can reflect the growth and development of fruit trees and are directly related to its potential yield. In this study, we develop a channel for automatic extraction of spectral and morphological features of apple trees using light detection and ranging (LiDAR) and multispectral imagery data from unmanned aerial vehicles. The contribution of spectral and morphological characteristics to the yield prediction of individual apple trees is discussed. With the combination of spectral and morphological features, an ensemble machine learning yield prediction model was developed by combining two widely used basic learners: support vector regression (SVR) and K-nearest neighbor (KNN). Then through extrapolating the ensemble model, the yield map was produced at the orchard level and individual tree level, respectively. The results show that the data processing channels developed in this study can accurately extract the morphological and spectral features of individual apple trees. Three features (Crown Volume 1, Ratio Vegetation Index, and CPA1) contribute most in apple tree yield prediction. The ensemble learning model outperforms all base learners with R2 = 0.813 for the validation and 0.758 for the test when using the selected three features. This study thus provides a practical example of predicting the yield of individual apple trees based on multi-source remote-sensing data and ensemble learning. [ABSTRACT FROM AUTHOR]

• In orchards, acquiring the maximum data possible is essential for growers. • Propose a deep learning model to help growers measure and acquire crop data. • Construct a large apple tree detection, segmentation, and measurement dataset. • The proposed model achieved a high count accuracy of 94.1% and a high segmentation accuracy of 97.1%. • The average measurement accuracy for the proposed model is over 92%. Manual measurement and visual inspection is a common practice for acquiring crop data in orchards and is a labor-intensive, time-consuming, and costly task. Accurate and rapid acquisition of crop data is vital for monitoring the dynamics of tree growth and optimizing farm management. In this work, we present a technique for orchard data acquisition and analysis that uses remote imagery acquired from unmanned aerial vehicles (UAVs) combined with deep learning convolutional neural networks to automatically detect and segment individual trees and measure the crown width, perimeter, and crown projection area of apple trees. By using an UAV platform, 50 high-resolution images of apple trees were collected from an orchard during dormancy (bare branches), and then each apple tree was detected by using a Faster R-CNN object detector. Based on these results, each tree was segmented by using a U-Net deep learning network. After convex tree boundaries were extracted from the semantic segmentation results by using an efficient pruning strategy, the crown parameters were automatically calculated, and the accuracy was compared with that obtained by manual delineation. The results show that the proposed remote sensing technique can be used to detect and count apple trees with precision and recall of 91.1% and 94.1%, respectively, segment their branches with an overall accuracy of 97.1%, and estimate crown parameter with an overall accuracy exceeding 92%. We conclude that this method not only saves labor by avoiding field measurements but also allows growers to dynamically monitor the growth of orchard trees. [ABSTRACT FROM AUTHOR]

To solve the problem of slow convergence seen in the traditional fine alignment algorithm based on linear Kalman filtering, a forward-forward backtracking fine alignment algorithm for SINS is proposed after reanalyzing the fine alignment model in this paper. First, the forward-forward backtracking fine alignment model in initial navigation frame was derived. The displacement vector of the carrier in the initial navigation frame solved by GNSS positioning was utilized as the observation of the fine alignment model. Second, under the premise of storing only part of the navigation data, the initial alignment convergence speed was improved by backtracking and reusing the navigation data. The experimental results of the simulation and vehicle tests showed that each backtracking alignment can improve the accuracy of the fine alignment to the performance requirements of the initial alignment, which proved the effectiveness and feasibility of the backtracking fine alignment algorithm proposed in this paper.

The vast majority of data obtained from sequence analysis of influenza A viruses (IAVs) have revealed that nonstructural 1 (NS1) proteins from H1N1 swine, H3N8 equine, H3N2 avian and the correspondent subtypes from dogs have a conserved four C-terminal amino acid motif when independent cross-species transmission occurs between these species. To test the influence of the C-terminal amino acid motifs of NS1 protein on the replication and virulence of IAVs, we systematically generated 7 recombinants, which carried naturally truncated NS1 proteins, and their last four C-terminal residues were replaced with PEQK and SEQK (for H1N1), EPEV and KPEI (for H3N8) and ESEV and ESEI (for H3N2) IAVs. Another recombinant was generated by removing the C-terminal residues by reverse genetics. Remarkably, the ESEI and KPEI motifs circulating in canines largely contributed efficient replication in cultured cells and these had enhanced virulence. In contrast, the avian ESEV motif was only responsible for high pathogenicity in mice. We examined the effects of these motifs upon interferon (IFN) induction. The 7 mutant viruses replicated in vitro in an IFN-independent manner, and the canine SEQK motif was able to induced higher levels of IFN-β in human cell lines. These findings shed further new light on the role of the four C-terminal residues in replication and virulence of IAVs and suggest that these motifs can modulate viral replication in a species-specific manner.

The upper respiratory tract is the initial site of SARS-CoV-2 infection. Nasal spike-specific secretory immunoglobulin A (sIgA) correlates with protection against Omicron breakthrough infection. We report that intranasal vaccination using human adenovirus serotype 5 (Ad5) vectored Omicron spike in people who previously vaccinated with ancestral vaccine could induce robust neutralizing sIgA in the nasal passage. Nasal sIgA was predominantly present in dimeric and multimeric forms and accounted for nearly 40% of total proteins in nasal mucosal lining fluids (NMLFs). A low-level IgG could also be detected in NMLFs but not IgM, IgD, and IgE. After a complete nasal wash, sIgA in the nasal passage could be replenished rapidly within a few hours. A comparison of purified paired serum IgA, serum IgG, and nasal sIgA from the same individuals showed that sIgA was up to 3-logs more potent than serum antibodies in binding to spikes and in neutralizing Omicron subvariants. Serum IgG and IgA failed to neutralize XBB and BA.2.86, while nasal sIgA retained potent neutralization against these newly emerged variants. Further analysis showed that sIgA was more effective than IgG or IgA in blocking spike-mediated cell-to-cell transmission and protecting hACE2 mice from XBB challenge. Using a sIgA monoclonal antibody as a reference, we estimated that the total nasal sIgA contains about 2.6-3.9% spike-specific sIgA in NMLFs collected approximately one month after intranasal vaccination. Our study provided insights for developing intranasal vaccines that can induce sIgA to build an effective and mutation-resistant first-line immune barrier against constantly emerging variants., (© 2024. The Author(s).)

Anode-free lithium metal batteries (AFLMBs) offer high-energy-density battery systems, but their commercial viability is hindered by irregular lithium dendrite growth and "dead Li" formation caused by current collector defects. This study employed filtered cathode vacuum arc (FCVA) technology to fabricate Cu current collectors (CCs) with a lithiophilic Zn 3 N 2 film. This advanced preparation process ensures an evenly distributed film that reduces the nucleation overpotential, homogenizes the interfacial electric field during plating/stripping processes, inhibits lithium dendrite growth, and forms a stable solid-electrolyte interphase (SEI). Our results show that the advanced Zn 3 N 2 @Cu CCs exhibit superior performance with a high CE of above 99.3% after 230 cycles at a current density of 0.5 mA cm -2 and an area capacity of 1 mAh cm -2 . Additionally, Li-Zn 3 N 2 @Cu||Li-Zn 3 N 2 @Cu symmetrical cells had a longer stable cycle time of over 1000 h than that of Li||Li and Li-Cu||Li-Cu symmetrical cells at a current density of 1 mA cm -2 and an area capacity of 2 mAh cm -2 . Compared with bare Cu CCs, the capacity retention rate is increased from 14.9 to 63.1% after 100 cycles with a 0.5C rate in the AFLMBs with LFP as the cathode. This work provides a pioneering, eco-friendly, and effective solution for the fabrication of anode CCs in AFLMBs, addressing a significant challenge in their commercial application.

Objective: To evaluate the acute effects of indoor and outdoor particulate matter on lung function and respiratory symptoms of college students in winter., Methods: A panel of 37 college students aged 19-21 in Wuhan were included and the investigation was carried out from 12/23/2009 to 01/05/2010. Daily morning/evening forced expiratory volume in one second (FEV1) and respiratory symptoms (cough, phlegm and runny) were measured and reported by subjects, respectively. Meanwhile, daily data of indoors and outdoors PM10, PM2.5, temperature, and relative humidity were collected. Generalized Estimating Equations (GEEs) were used to estimate the association between particulate matters exposure and respiratory symptoms and FEV1)., Results: Average daily concentrations of indoor, outdoor PM2.5 during the study period were (110.6 ± 42.3), (143.5 ± 51.2) µg/m³, (148.2 ± 43.2) and (239.1 ± 71.3) µg/m³ for indoor, outdoor PM10, respectively. Outdoor exposure to PM2.5 on lag 0 had little effect on evening FEV1). However, researchers observed a significant lagging effect (lag 1 d) and accumulative effect (lag 0-1 d and lag 0-2 d). A rise in the PM2.5 concentration of 10 µg/m³ resulted in the change of evening FEV1) of -0.28% (95% CI: -0.52%, -0.03%), -0.45% (95% CI: -0.81%, -0.08%) and -0.63% (95% CI: -1.15%, -0.11%), respectively. For respiratory symptoms of coughing up phlegm, 10 mg/m³ increase of indoor/outdoor PM2.5 concentration were associated with odds ratio of 1.18 (95% CI: 1.02-1.36) and 1.08 (95% CI: 0.97-1.19), respectively. Moreover, risk of coughing up phlegm increased with lagging time, and accumulative time of indoor and outdoor PM2.5 and PM10., Conclusion: Our study suggested that short-term exposure to particulate matters in winter was significantly associated with acute changes of respiratory symptoms and FEV1) of college students in Wuhan. Moreover, the effects of particulate matters tended to be larger as the increase of lagged and accumulative days.

The effect of ambient particulate matters on human health is of great concern. Numerous epidemiological studies have revealed that particulate matters were associated with increased population mortality. Moreover, many studies found that season and temperature might modify the effect of particles on mortality. This paper summarized the potential effect modification of season and temperature and the possible mechanism, so as to provide certain evidence and reference for the future relevant studies.