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Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among features. However, feature-selection methods that satisfy both requirements are lacking. To address this issue, in this study, a novel method, the continuous wavelet projections algorithm (CWPA), was developed, which has advantages of both continuous wavelet analysis (CWA) and the successive projections algorithm (SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content (R² = 0.8521) and equivalent water thickness (R² = 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data. [ABSTRACT FROM AUTHOR]

The CRISPR/Cas9 system has been used in a wide range of applications in the production of gene-edited animals and plants. Most efforts to insert genes have relied on homology-directed repair (HDR)-mediated integration, but this strategy remains inefficient for the production of gene-edited livestock, especially monotocous species such as cattle. Although efforts have been made to improve HDR efficiency, other strategies have also been proposed to circumvent these challenges. Here we demonstrate that a homology-mediated end-joining (HMEJ)-basedmethod can be used to create gene-edited cattle that displays precise integration of a functional gene at the ROSA26 locus. We found that the HMEJ-based method increased the knock-in efficiency of reporter genes by eightfold relative to the traditionalHDR-basedmethod in bovine fetal fibroblasts. Moreover, we identified the bovine homology of themouse Rosa26 locus that is an accepted genomic safe harbor and produced three live-borngene-edited cattlewith higher rates of pregnancy and birth, compared with previous work. These gene-edited cattle exhibited predictable expression of the functional gene natural resistance-associated macrophage protein-1 (NRAMP1), a metal ion transporter that should and, in our experiments does, increase resistance to bovine tuberculosis, one of the most detrimental zoonotic diseases. This research contributes to the establishment of a safe and efficient genome editing system and provides insights for gene-edited animal breeding. [ABSTRACT FROM AUTHOR]

Detection of yellow rust using hyperspectral data is of practical importance for disease control and prevention. As an emerging spectral analysis method, continuous wavelet analysis (CWA) has shown great potential for the detection of plant diseases and insects. Given the spectral interval of airborne or spaceborne hyperspectral sensor data differ greatly, it is important to understand the impact of spectral interval on the performance of CWA in detecting yellow rust in winter wheat. A field experiment was conducted which obtained spectral measurements of both healthy and disease-infected plants. The impacts of the mother wavelet type and spectral interval on disease detection were analyzed. The results showed that spectral features derived from all four mother wavelet types exhibited sufficient sensitivity to the occurrence of yellow rust. The Mexh wavelet slightly outperformed the others in estimating disease severity. Although the detecting accuracy generally declined with decreasing of spectral interval, relatively high accuracy levels were maintained (R²>0.7) until a spectral interval of 16 nm. Therefore, it is recommended that the spectral interval of hyperspectral data should be no larger than 16 nm for the detection of yellow rust. The relatively loose spectral interval requirement permits extensive applications for disease detection with hyperspectral imagery. [ABSTRACT FROM AUTHOR]

Somatic cell nuclear transfer (SCNT)-mediated reprogramming is a rapid, efficient, and sophisticated process that reprograms differentiated somatic cells to a pluripotent state. However, many factors in this elaborate reprogramming process remain largely unknown. Here, we report that the microRNA (miR) miR-125b is an important component of SCNT-mediated reprogramming. Luciferase reporter assay, quantitative PCR, and Western blotting demonstrated that miR-125b directly binds the 3'-untranslated region of SUV39H1, encoding the histone-lysine N-methyltransferase SUV39H1, to down-regulate histone H3 lysine-9 tri-methylation (H3K9me3) in SCNT embryos. Furthermore, the miR-125b/SUV39H1 interaction induced loss of SUV39H1-mediated H3K9me3, caused heterochromatin relaxation, and promoted the development of SCNT embryos. Transcriptome analyses of SCNT blastomeres indicated that HNF1 homeobox B (HNF1B), a gene encoding a transcription factor downstream of and controlled by the miR-125b/ SUV39H1 axis, is important for conferring developmental competence on preimplantation embryos. We conclude that miR-125b promotes SCNT-mediated nuclear reprogramming by targeting SUV39H1 to decrease the deposition of repressive H3K9me3 modifications. [ABSTRACT FROM AUTHOR]

Core-shell metal organic framework (MOF) crystals have attracted increasing attention due to their specific structure and remarkable properties. Herein, we demonstrate a facile approach for the synthesis of uniform multilayered core-shell MOF crystals including ZIF-67@ZIF-8@ZIF-67 and ZIF-8@ZIF-67@ZIF-8 for the first time, by adopting the condition for the preparation of relatively larger sized crystals to fabricate the shells on the surface of relatively smaller sized seeds without any auxiliary condition. Compared with the control experiments opposite our strategy, there are two dominant factors determining the successful synthesis: (i) the homological feature between ZIF-8 and ZIF-67 favors the heterogeneous nucleation and continuous crystal growth on the surface of seeds; (ii) by controlling a relatively lower nucleation rate and a longer crystal growth stage, it enables the shell formation on the surface of the seed but avoids other monocomponent crystals generated in solution. In addition, the size of the core and the thickness of the shell could also be easily controlled by using the seeds in different size and varying the molar feeding ratio of Zn2+/Co2+, respectively, during the preparation process. Furthermore, such a strategy is also expected to extend to the synthesis of other multilayered core-shell MOFs. [ABSTRACT FROM AUTHOR]

Three sea buckthorn leaf tea products, namely, tea dried at room temperature (SDRIED), conventionally processed green tea (SGREEN) and black tea (SBLACK), were compared for their effects on human fecal microflora and the levels of related nutrients. Content analysis confirmed higher total polysaccharides for SGREEN (165.8 ± 0.1 g·kg-1) than for SBLACK (100.0 ± 0.1 g·kg-1) and SDRIED (115.8 ± 0.1 g·kg-1), higher total quercetin for SGREEN (6.0 ± 0.2 g·kg-1) and SDRIED (7.7 ± 0.2 g·kg-1) than for SBLACK (2.4 ± 0.1 g·kg-1), and higher total gallic acid for SBLACK (0.60 ± 0.01 g·kg-1) than for SGREEN (0.46 ± 0.01g·kg-1) and SDRIED (0.07 ± 0.01 g·kg-1). An in vitro digestion assay demonstrated that the order of nutrient contents remained unchanged after digestion. Furthermore, an in vitro fermentation assay indicated that only SGREEN treatment could increase the content of the probiotic Bifidobacterium and decrease the content of the pathogenic Clostridium perfringens simultaneously. These findings show that green tea processing technology is more suitable for making sea buckthorn leaf tea. For the first time, improved fecal microflora rather than antioxidant activity was selected to evaluate different leaf tea products. [ABSTRACT FROM AUTHOR]

Powdery mildew, caused by the fungus Blumeria graminis, is a major winter wheat disease in China. Accurate delineation of powdery mildew infestations is necessary for site-specific disease management. In this study, high-resolution multispectral imagery of a 25 km2 typical outbreak site in Shaanxi, China, taken by a newly-launched satellite, SPOT-6, was analyzed for mapping powdery mildew disease. Two regions with high representation were selected for conducting a field survey of powdery mildew. Three supervised classification methods—artificial neural network, mahalanobis distance, and maximum likelihood classifier—were implemented and compared for their performance on disease detection. The accuracy assessment showed that the ANN has the highest overall accuracy of 89%, following by MD and MLC with overall accuracies of 84% and 79%, respectively. These results indicated that the high-resolution multispectral imagery with proper classification techniques incorporated with the field investigation can be a useful tool for mapping powdery mildew in winter wheat. [ABSTRACT FROM AUTHOR]

There is much evidence suggesting that CCL5 is one of the chemoattractant cytokines involved in diabetes mellitus (DM) with diffuse large B-cell lymphoma (DLBCL). However, the pathological impact is unclear. In the current study, in order to improve understanding regarding the role of CCL5 in DM with DLBCL, the expression levels of CCL5 mRNA were examined in normal B cells, human DLBCL cell lines (Ly1, Ly8 and Ly10) and a mouse DLBCL cell line (A20), as well as those in cells cultured with either 5 or 30 mmol/l glucose. A20-CCL5+ (CCL5 overexpression) and A20-CCL5- (CCL5 knockdown) subclones were obtained through cell transduction with a lentiviral vector, and were subcutaneously injected into BALB/c DM mice and normal mice. Tumor growth was observed by calculating the tumor volume. The results demonstrated that CCL5 mRNA levels in DLBCL cells were significantly higher than those in the normal cells (P<0.05); and levels in DLBCL cells in 30 mmol/l Glu were significantly higher than in those of DLBCL cells in 5 mmol/l Glu (P<0.05). A20-CCL5+ cells led to tumor formation in DM mice compared with A20 and A20-CCL5- cells. These results indicate that high levels of CCL5 expression may accelerate DLBCL formation in DM. [ABSTRACT FROM AUTHOR]

Powdery mildew, caused by the fungus Blumeria graminis, is a major winter wheat disease in China. Accurate delineation of powdery mildew infestations is necessary for site-specific disease management. In this study, high-resolution multispectral imagery of a 25 km² typical outbreak site in Shaanxi, China, taken by a newly-launched satellite, SPOT-6, was analyzed for mapping powdery mildew disease. Two regions with high representation were selected for conducting a field survey of powdery mildew. Three supervised classification methods—artificial neural network, mahalanobis distance, and maximum likelihood classifier—were implemented and compared for their performance on disease detection. The accuracy assessment showed that the ANN has the highest overall accuracy of 89%, following by MD and MLC with overall accuracies of 84% and 79%, respectively. These results indicated that the high-resolution multispectral imagery with proper classification techniques incorporated with the field investigation can be a useful tool for mapping powdery mildew in winter wheat. [ABSTRACT FROM AUTHOR]

Colloidal clay particle transport under saturated conditions is believed to be controlled by its interactions with the surrounding environment. The dominating forces among these interactions are electrostatic forces that are determined by colloidal clay particle and porous medium surface charge density and Lifshitz–van der Waals forces that are determined by colloidal clay particle and porous medium surface thermodynamic properties. Electrostatic forces are greatly affected by solution chemistry in terms of solution ionic strength and pH. In this research, electrostatic and Lifshitz–van der Waals forces of natural colloidal clay particles with a model porous medium of silica sand were quantified at different ionic strength and pH conditions. At the same time, colloidal clay particle transport in the model medium of silica sand was conducted in a laboratory column. The maximum electrostatic forces, FEL (max), which occurred when the separation distance between colloidal clay particles and the porous medium was in the range of the sum of the double layer thicknesses of the colloidal clay particles and the porous medium, was found to be the determinant factor for colloidal clay particle deposition in the porous medium. Colloidal clay particle desorption in the porous media was related to the net effect of attractive Lifshitz–van der Waals forces and repulsive electrostatic forces, evaluated at the equilibrium distance where physical contact between the colloidal clay particle and silica sand actually occurred (i.e., affix force). Higher colloidal clay particle desorption was found to coincide with smaller affix force values. [ABSTRACT FROM AUTHOR]

Aberrant epigenetic reprogramming is a major factor of developmental failure of cloned embryos. Histone H3 lysine 27 trimethylation (H3K27me3), a histone mark for transcriptional repression, plays important roles in mammalian embryonic development and induced pluripotent stem cell (iPSC) generation. The global loss of H3K27me3 marks may facilitate iPSC generation in mice and humans. However, the H3K27me3 level and its role in bovine somatic cell nuclear transfer (SCNT) reprogramming remain poorly understood. Here, we show that SCNT embryos exhibit global H3K27me3 hypermethylation from the 2- to 8-cell stage and that its removal by ectopically expressed H3K27me3 lysine demethylase (KDM)6A greatly improves nuclear reprogramming efficiency. In contrast, H3K27me3 reduction by H3K27me3 methylase enhancer of zeste 2 polycomb repressive complex knockdown or donor cell treatment with the enhancer of zeste 2 polycomb repressive complex-selective inhibitor GSK343 suppressed blastocyst formation by SCNT embryos. KDM6A overexpression enhanced the transcription of genes involved in cell adhesion and cellular metabolism and X-linked genes. Furthermore, we identified methyl-CpG-binding domain protein 3-like 2, which was reactivated by KDM6A, as a factor that is required for effective reprogramming in bovines. These results show that H3K27me3 functions as an epigenetic barrier and that KDM6A overexpression improves SCNT efficiency by facilitating transcriptional reprogramming. [ABSTRACT FROM AUTHOR]

Melatonin and vitamin C are powerful antioxidants that improve the reprogramming efficiency of induced pluripotent stem cells (iPSCs). However, the effects of the combined treatment of vitamin C and melatonin on the differentiation of embryonic stem cells (ESCs) have not yet been examined. In this study, we showed that melatonin synergizes with vitamin C to derail exit from pluripotency of mouse ESCs. This effect is related to the increased uptake of dehydroascorbate, the oxidized form of vitamin C, through glucose transporter 1 (Glut1) transporter, which in turn, is upregulated by melatonin treatment. Analysis of the cell signaling pathway profiling systems and specific pathway inhibition indicated that melatonin enhances Glut1 expression by activating the PI3K/AKT and MAPK/ERK signaling pathways. Our findings provide a theoretical basis for application of melatonin in research on ESCs and iPSCs and for further investigation of the effect of combinatorial compounds on cell reprogramming.--Wu, H., Song, C., Zhang, J., Zhao, J., Fu, B., Mao, T., Zhang, Y. Melatonin-mediated upregulation of GLUT1 blocks exit from pluripotency by increasing the uptake of oxidized vitamin C in mouse embryonic stem cells. [ABSTRACT FROM AUTHOR]

Bound states in the continuum (BICs) offer novel mechanisms to boost the quality factor (Q-factor) of resonances. Unfortunately, current studies on chiral BICs metasurfaces suffer from a fundamental trade-off between Q-factor and circular dichroism (CD), presenting a significant hurdle that severely limits the independent control between CD and Q-factors. Here, 3D plasmonic metasurfaces are numerically demonstrated that overcome the trade-off and offer high-Q quasi-BIC resonances (Q ≈ 938) with strong CD (≈0.67) in the mid-infrared. These metasurfaces are made of integrated-resonance units consisting of a twisted vertical split-ring resonator (VSRR) and a wall. Importantly, this dissimilar dimer configuration unlocks a new degree of freedom to decouple the Q-factor and CD, that is, the Q-factor and CD can be relatively independently manipulated by the height of the wall and the twisted angle of the VSRR, respectively. These results provide novel paradigms to manipulate advanced chiroptical responses, with various applications that require strong CD with enhanced light-matter interaction. [ABSTRACT FROM AUTHOR]

The objective of this study was to measure apparent total tract digestibility (ATTD) of Ca and P as well as reproductive performance in late gestation and lactating sows supplemented with a novel phytase and to compare the response to phytase supplementation between late gestation and lactating sows. A total of 45 late gestation sows and 45 lactating sows were used in experiments 1 and 2, respectively, in a completely randomized design. The sows were provided with a control diet or the control diet supplemented with 187.5 or 375 FYT phytase/kg feed for 10 days. The diets were prepared according to the formulas in use for production but without any inorganic P supplement. Titanium dioxide was included at 3 g/kg feed as an indigestible marker. Each dietary treatment was replicated with 15 sows individually housed in farrowing stalls. The sows were allowed to adapt to the experimental diets for 5 days before a 5-d fecal collection by grab sampling, and the performance of the sows and their litters were measured until weaning. The results showed that the ATTD of Ca increased linearly (P < 0.001), while the ATTD of P increased both linearly and quadratically (P < 0.01) with increasing supplementation of phytase in both late gestation and lactating sows. There was no significant effect of phytase on the ATTD of dry matter, crude protein, and gross energy, and the performance of the sows and their progenies. The phytase added at 187.5 and 375 FYT/kg feed released 0.07% and 0.10% digested P, respectively, in late gestation sows, which compared with 0.09% and 0.12% digested P in lactating sows. In conclusion, a novel phytase at 187.5–375 FYT/kg feed could release 0.07–0.12% digestible P for sows. It appeared that using the P digestibility values of feed ingredients listed by NRC to formulate a diet for sows might overestimate dietary P supply and a greater response to phytase supplementation could be expected in lactating sows than in late gestation sows. [ABSTRACT FROM AUTHOR]

In mammals, sperm-borne regulators can be transferred to oocytes during fertilization and have different effects on the formation of pronuclei, the first cleavage of zygotes, the development of preimplantation embryos and even the metabolism of individuals after birth. The regulatory role of sperm microRNAs (miRNAs) in the development of bovine preimplantation embryos has not been reported in detail. By constructing and screening miRNA expression libraries, we found that miR-202 was highly enriched in bovine sperm. As a target gene of miR-202, co-injection of SEPT7 siRNA can partially reverse the accelerated first cleavage of bovine embryos caused by miR-202 inhibitor. In addition, both a miR-202 mimic and SEPT7 siRNA delayed the first cleavage of somatic cell nuclear transfer (SCNT) embryos, suggesting that miR-202-SEPT7 mediates the delay of first cleavage of bovine embryos. By further exploring the relationship between miR-202/SEPT7, HDAC6 and acetylated α-tubulin during embryonic development, we investigated how sperm-borne miR-202 regulates the first cleavage process of bovine embryos by SEPT7 and demonstrate the potential of spermborne miRNAs to improve the efficiency of SCNT. [ABSTRACT FROM AUTHOR]

Aberrant epigenetic reprogramming often results in developmental defects in somatic cell nuclear transfer (SCNT) embryos during embryonic genome activation (EGA). Bovine eight-cell SCNT embryos exhibit global hypermethylation of histone H3 lysine 9 tri- and di-methylation (H3K9me3/2), but the intrinsic reason for this remains elusive. Here, we provide evidence that two H3K9 demethylase genes, lysine-specific demethylase 4D (KDM4D) and 4E (KDM4E), are related to active H3K9me3/2 demethylation in in vitro fertilized (IVF) embryos and are deficiently expressed in cloned embryos at the time of EGA. Moreover, KDM4E plays a more crucial role in IVF and SCNT embryonic development, and overexpression of KDM4E can restore the global transcriptome, improve blastocyst formation and increase the cloning efficiency of SCNT embryos. Our results thereby indicate that KDM4E can function as a crucial epigenetic regulator of EGA and as an internal defective factor responsible for persistent H3K9me3/2 barriers to SCNT-mediated reprogramming. Furthermore, we show that interactions between RNA and KDM4E are essential for H3K9 demethylation during EGA. These observations advance the understanding of incomplete nuclear reprogramming and are of great importance for transgenic cattle procreation. [ABSTRACT FROM AUTHOR]

With the development of hyperspectral technology, to establish an effective spectral data compressive reconstruction method that can improve data storage, transmission, and maintaining spectral information is critical for quantitative remote sensing research and application in vegetation. The spectral adaptive grouping distributed compressive sensing (AGDCS) algorithm is proposed, which enables a distributed compressed sensing reconstruction of plant hyperspectral data. The spectral characteristics of hyperspectral data are analyzed and the joint sparse model is constructed. The spectral bands are adaptively grouped and the hyperspectral data are compressed and reconstructed on the basis of grouping. The experimental results showed that, compared with orthogonal matching pursuit (OMP) and gradient projection for sparse reconstruction (GPSR), AGDCS can significantly improve the visual effect of image reconstruction in the spatial domain. The peak signal-to-noise ratio (PSNR) at a low sampling rate (the sampling rate is lower than 0.2) increases by 13.72 dB than OMP and 1.66 dB than GPSR. In the spectral domain, the average normalized root mean square error, the mean absolute percentage error, and the mean absolute error of AGDCS is 35.38%, 31.83%, and 33.33% lower than GPSR, respectively. Additionally, AGDCS can achieve relatively high reconstructed efficiency. [ABSTRACT FROM AUTHOR]

The development of a bacteria-inducible expression system has several advantages compared with persistent expression of anti-bacterial proteins in milk to prevent and treat mastitis. The present study determined whether mastitis responsive promoters could regulate enhanced green fluorescent protein (EGFP) expression in goat mammary epithelial cells (GMECs) in response to challenges with Escherichia coli. Staphylococcus aureus or Streptococcus agalactiae. The level of expression of interleukin (IL)-1α was significantly increased in GMECs challenged with E. coli, S. aureus or S. agalactiae compared with untreated GMECs. 1L- 1β was induced by £ coli and S. aureus, while Toll-like receptor 2 (TLR2) was induced by £ coli only. GMECs were transfected with IL-1α, IL-1β and TLR2 promoter-EGFP reporter gene lentiviral expression vectors and the levels of expression of EGFP were measured by flow cytometry and Western blot analysis after bacteria! challenge. EGFP expression driven by the IL-1α and IL-1β promoters was higher in GMECs challenged with £ coli, S. aureus or S. agalactiae than in untreated GMECs. There were no differences in EGFP expression driven by the TLR2 promoter between GMECs challenged with S. aureus or S. agalactiae and untreated GMECs, but EGFP expression was significantly increased in GMECs challenged with £ coli. Overall, these results indicate that the promoters of some bacteria-inducible genes can regulate EGFP expression in GMECs in response to bacterial challenges. This bacteria-inducible expression strategy could be used for production of mastitis resistant animals by regulating the expression of anti-bacterial proteins in the mammary gland. [ABSTRACT FROM AUTHOR]

Ni-promoted tetramethylammonium tetrathiomolybdate precursor was prepared by the aqueous solution precipitation method using (NH4)2MoS4, (CH3)4NBr and NiCl2.6H2O as raw materials. Carbon-containing Ni–Mo sulfide nanospheres, namely Ni/C1–MoS2, were obtained by ex situ thermal decomposition of the precursor under N2 atmosphere. Energy dispersive X-ray spectroscopy (EDS), low temperature N2 adsorption (BET method), X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) techniques were employed to characterize these as–synthesized sulfide particles. The results showed that the average size of solid Ni–Mo sulfide nanospheres, with surface composition MoNi0.40S0.73C1.43, is 75 nm and the solid structure leads to low surface area of Ni/C1–MoS2. In addition, the introduction of methyl chain improved the dispersion of nickel phases and resulted in C/Mo ratio, 1.4. By comparison with catalytic performance of the Ni/MoS2 catalyst counterpart, Ni/C1–MoS2 revealed lower HDS activity but higher direct desulfurization (DDS) selectivity. Lower stacking number of MoS2 slabs (5 layers) and shorter slabs length of MoS2 slabs (6 nm) explained higher DDS selectivity satisfactorily. The formation of carbon-containing Ni–Mo sulfide nanospheres was possibly due to surfactant effect of tetramethylammonium cations and the potential measure to increase their surface area was discussed as well in this work. [ABSTRACT FROM AUTHOR]