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Microwave photonic real-time Fourier transformation (RTFT) processing based on optical dispersion is a promising solution for microwave spectrum analysis. However, it usually brings the drawbacks of limited frequency resolution and large processing latency. Here, we demonstrate a low-latency microwave photonic RTFT processing based on bandwidth slicing and equivalent dispersion. The input RF signal is first divided into different channels with the help of bandwidth slicing technique, and then finely analyzed by the fiber-loop based frequency-to-time mapping. In the proof-of-concept experiment, a 0.44-m fiber-loop offers an equivalent dispersion as high as 6 × 10 5  ps/nm with a small transmission latency of 50 ns. As a result, we can realize a wide instantaneous bandwidth of 1.35 GHz, a high frequency resolution of approximately 20 MHz, and a high acquisition frame rate of approximately 450 MHz, together with a total latency of less than 200 ns.

Senile plaques are a pathological hallmark of Alzheimer's disease (AD), yet the mechanism underlying their generation remains unknown. Beta-amyloid peptide (Aβ) is a major component of senile plaques. We analysed AD brain tissues with histochemistry, immunohistochemistry and fluorescence imaging to examine the neural, vascular or blood Aβ contribution to senile plaque development. We found little neural marker co-expression with plaque Aβ, while co-expression of blood markers, such as Haemin and ApoE, was abundant. The plaque cores were structured with vascular and glial proteins outside and blood metabolites inside, co-localizing with a characteristic of Hoechst staining-independent blue autofluorescence. Erythrocyte-interacting Aβ is linked to coagulation, elevated calcium and blue autofluorescence, and it is associated with intravascular haemolysis, atherosclerosis, cerebral amyloid angiopathy, microaneurysm, and often with Cathepsin D co-expression. We identified microaneurysms as major sites of amyloid formation. Our data suggest that senile plaques arise from Aβ- and Cathepsin D-enriched mixtures leaking out during intravascular haemolysis and microaneurysm rupture., (© 2022 Federation of European Biochemical Societies.)

In this study, a novel supramolecular solvent based on surface-active ionic liquid was prepared and used as an extraction solvent for dispersive liquid-liquid microextraction of four triazine herbicides in tea samples. The formation mechanism, microstructure and physicochemical properties of supramolecular solvent were studied. Some parameters, including the molar ratio of surface-active ionic liquid to tetrahydrofuran, volume of supramolecular solvent, vortex time, pH of sample solution, type and amount of salt, were investigated and optimized. The good linearities (r > 0.9990) for the analytes were obtained. The limits of detection and quantification for triazine herbicides were in the range of 1.7-2.1 μg kg -1 and 5.6-7.1 μg kg -1 , respectively. The spiked recoveries were 80.0-119.9 %. The supramolecular solvent prepared in this study has the advantages of simple preparation process, low viscosity and good dispersibility. It can be used for the extraction and enrichment of trace triazine herbicides in tea samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

We characterize the differential modal group delay (DMGD) arising in few-mode fibers (FMFs) based on the digital re-sampling technique, which is commonly used in current digital signal processing flow at the receiver-side. When the DMGD of a 291-m two-mode fiber is characterized over the C-band by using a 500-Mb/s non-return-to-zero (NRZ) signal and 1-GSa/s real-time oscilloscope, the experimental results are consistent with the DMGD obtained from the traditional time-of-flight (TOF) method. However, the wide-bandwidth instruments of the traditional TOF method can be replaced by cheap ones with a bandwidth of only a few hundred MHz, but the same temporal precision is achieved. Moreover, our proposed DMGD characterization method is not limited by the number of guided modes arising in the FMF, together with the capability to obtain both the DMGD value and its sign between two arbitrary guided modes.

Tunable microwave dispersion is highly desired for a wide field of microwave signal processing. However, a conventional microwave dispersive delay line usually suffers from either a small dispersion value or a narrow operation bandwidth. Here, we experimentally demonstrate the optically magnified dispersion of a microwave signal with a wide and flexible tunable range, based on a bandwidth-scaling microwave photonic system. The obtained microwave dispersion can therefore be magnified from the corresponding optical dispersion with a magnification factor that can be continuously tuned from 10,000 to 85,000. Meanwhile, a proof-of-concept experiment that includes both compression and stretching of chirped microwave pulses is reported. Microwave dispersion from 1.34 ns/GHz to 10.92 ns/GHz can be secured by the corresponding magnification of an optical dispersion value of 16 ps/nm.

The state and behaviour of a cell can be influenced by both genetic and environmental factors. In particular, tumour progression is determined by underlying genetic aberrations 1-4 as well as the makeup of the tumour microenvironment 5,6 . Quantifying the contributions of these factors requires new technologies that can accurately measure the spatial location of genomic sequence together with phenotypic readouts. Here we developed slide-DNA-seq, a method for capturing spatially resolved DNA sequences from intact tissue sections. We demonstrate that this method accurately preserves local tumour architecture and enables the de novo discovery of distinct tumour clones and their copy number alterations. We then apply slide-DNA-seq to a mouse model of metastasis and a primary human cancer, revealing that clonal populations are confined to distinct spatial regions. Moreover, through integration with spatial transcriptomics, we uncover distinct sets of genes that are associated with clone-specific genetic aberrations, the local tumour microenvironment, or both. Together, this multi-modal spatial genomics approach provides a versatile platform for quantifying how cell-intrinsic and cell-extrinsic factors contribute to gene expression, protein abundance and other cellular phenotypes., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Electrolysis of seawater can be a promising technology, but chloride ions in seawater can lead to adverse side reactions and the corrosion of electrodes. A new transition metal boride-based self-supported electrocatalyst was prepared for efficient seawater electrolysis by directly soaking nickel foam (NF) in a mixture of phenolic resin (PR) and boron carbide (B 4 C), followed by an 800 °C annealing. During PR carbonization process, the reaction of B 4 C and NF generated nickel boride (Ni x B) with high catalytic activity, while PR-derived carbon coating was doped with boron atoms from B 4 C (B-C PR ). The B-C PR coating fixed Ni x B/B 4 C particles in the frames and holes to improve the space utilization of NF. Meanwhile, the B-C PR coating effectively protected the catalyst from the corrosion by seawater and facilitates the transport of electrons. The optimal Ni x B/B 4 C/B-C PR /NF required 1.50 and 1.58 V to deliver 100 and 500 mA cm -2 , respectively, in alkaline natural seawater for the oxygen evolution reaction., (© 2021 Wiley-VCH GmbH.)

The improvement of cold adaptation has contributed to the increased growing area of rice. Standing variation and de novo mutation are distinct natural sources of beneficial alleles in plant adaptation. However, the genetic mechanisms and evolutionary patterns underlying these sources in a single population during crop domestication remain elusive. Here we cloned the CTB2 gene, encoding a UDP-glucose sterol glucosyltransferase, for cold tolerance in rice at the booting stage. A single standing variation (I408V) in the conserved UDPGT domain of CTB2 originated from Chinese Oryza rufipogon and contributed to the cold adaptation of Oryza sativa ssp. japonica. CTB2 is located in a 56.8 kb region, including the previously reported gene CTB4a in which de novo mutation arose c. 3200 yr BP in Yunnan province, China, conferring cold tolerance. Standing variation of CTB2 and de novo mutation of CTB4a underwent stepwise selection to facilitate cold adaptation to expand rice cultivation from high-altitude to high-latitude regions. These results provide an example of stepwise selection on two kinds of variation and describe a new molecular mechanism of cold adaptation in japonica rice., (© 2021 The Authors. New Phytologist © 2021 New Phytologist Foundation.)

Ruminal microbiota changes frequently with high grain diets and the occurrence of subacute ruminal acidosis (SARA). A grain-induced goat model of SARA, with durations of a significant decrease in the rumen pH value to less than 5.6 and an increase in the rumen lipopolysaccharides concentration, is constructed for real-time monitoring of bacteria alteration. Using 16 S rRNA gene sequencing, significant bacterial differences between goats from the SARA and healthy groups are identified at every hour for six continuous hours after feeding. Moreover, 29 common differential genera between two groups over 6 h after feeding are all related to the altered pH and lipopolysaccharides. Transplanting the microbiota from donor goats with SARA could induce colonic inflammation in antibiotic-pretreated mice. Overall, significant differences in the bacterial community and rumen fermentation pattern between the healthy and SARA dairy goats are real-time monitored, and then tested using ruminal microbe transplantation to antibiotic-treated mice.

The need to effectively and selectively remove radioactive 137 Cs and 90 Sr from nuclear waste solutions persists to mitigate their environmental mobility and high radiotoxicity. Because it is difficult to effectively remove them from acidic environments that degrade most sorbents, new sorbent materials are highly desirable. Here, efficient removal of Cs + and Sr 2+ is achieved by the composite of layered tin sulfide (Me 2 NH 2 ) 4/3 (Me 3 NH) 2/3 Sn 3 S 7 ·1.25H 2 O (FJSM-SnS) and polyacrylonitrile (PAN) (FJSM-SnS/PAN). The granulous composite possesses regular particle morphology and good mechanical strength as an engineered form. It shows excellent acid-base and γ-irradiation resistance, high maximum adsorption capacities ( q m ) of 296.12 and 62.88 mg/g for Cs + and Sr 2+ ions, respectively, and high selectivity even in the presence of excess Na + ions or using lake water. Impressively, q m Cs of FJSM-SnS/PAN reaches 89.29 mg/g under even acidic conditions (pH = 2.5). The column loaded with FJSM-SnS/PAN granules exhibits high removal rates ( R ) toward low-concentration Cs + and Sr 2+ ions under both neutral and acidic conditions. Moreover, the composite can be recycled and reused with high R Cs and R Sr . This work highlights the great potential of metal sulfide ion-exchangers in engineered form for the efficient removal of Cs + or Sr 2+ ions, especially under acidic conditions, for radionuclide remediation.

An indium selenide [Bmmim]6[In10Se16Cl4]·(MIm)2 (Bmmim = 1-butyl-2,3-dimethylimidazolium, MIm = 1-methylimidazole) cluster has been synthesized and characterized. The discrete T3 cluster could be stably dispersed in dimethyl sulfoxide, exhibiting photocatalytic hydrogen evolution activity at least six times that of the pristine in the solid state due to the exposure of more active sites.

Aging is a risk factor for chronic kidney disease (CKD) and is itself associated with alterations in renal structure and function. There are no specific interventions to attenuate age-dependent renal dysfunction and the mechanism(s) responsible for these deficits have not been fully elucidated. In this study, male Fischer 344 rats, which develop age-dependent nephropathy, were feed a casein- or soy protein diet beginning at 16 mon (late life intervention) and renal structure and function was assessed at 20 mon. The soy diet did not significantly affect body weight, but was renoprotective as assessed by decreased proteinuria, increased glomerular filtration rate (GFR) and decreased urinary kidney injury molecule-1 (Kim-1). Renal fibrosis, as assessed by hydroxyproline content, was decreased by the soy diet, as were several indicators of inflammation. RNA sequencing identified several candidates for the renoprotective effects of soy, including decreased expression of Twist2, a basic helix-loop-helix transcription factor that network analysis suggest may regulate the expression of several genes associated with renal dysfunction. Twist2 expression is upregulated in the aging kidney and the unilateral ureteral obstruction of fibrosis; the expression is limited to distal tubules of mice. Taken together, these data demonstrate the renoprotective potential of soy protein, putatively by reducing inflammation and fibrosis, and identify Twist2 as a novel mediator of renal dysfunction that is targeted by soy.

Ischemic stroke is a devastating neurological disease that can cause permanent brain damage, but to date, few biomarkers are available to reliably assess the severity of injury during acute onset. In this study, quantitative proteomic analysis of ischemic mouse brain detected the increase in expression levels of clusterin (CLU) and cystatin C (CST3). Since CLU is a secretary protein, serum samples (n = 70) were obtained from acute ischemic stroke (AIS) patients within 24 h of stroke onset and together with 70 matched health controls. Analysis of CLU levels indicated significantly higher levels in AIS patients than healthy controls (14.91 ± 4.03 vs. 12.79 ± 2.22 ng/L; P = 0.0004). Analysis of serum CST3 also showed significant increase in AIS patients as compared with healthy controls (0.90 ± 0.19 vs. 0.84 ± 0.12 ng/L; P = 0.0064). The serum values of CLU were also positively correlated with the NIH Stroke Scale (NIHSS) scores, the time interval after stroke onset, as well as major stroke risk factors associated with lipid profile. These data demonstrate that elevated levels of serum CLU and CST3 are independently associated with AIS and may serve as peripheral biomarkers to aid clinical assessment of AIS and its severity. This pilot study thus contributes to progress toward preclinical proteomic screening by using animal models and allows translation of results from bench to bedside.

Every two years groups worldwide participate in the Critical Assessment of Protein Structure Prediction (CASP) experiment to blindly test the strengths and weaknesses of their computational methods. CASP has significantly advanced the field but many hurdles still remain, which may require new ideas and collaborations. In 2012 a web-based effort called WeFold, was initiated to promote collaboration within the CASP community and attract researchers from other fields to contribute new ideas to CASP. Members of the WeFold coopetition (cooperation and competition) participated in CASP as individual teams, but also shared components of their methods to create hybrid pipelines and actively contributed to this effort. We assert that the scale and diversity of integrative prediction pipelines could not have been achieved by any individual lab or even by any collaboration among a few partners. The models contributed by the participating groups and generated by the pipelines are publicly available at the WeFold website providing a wealth of data that remains to be tapped. Here, we analyze the results of the 2014 and 2016 pipelines showing improvements according to the CASP assessment as well as areas that require further adjustments and research.

With the expansion of genomics and proteomics data aided by the rapid progress of next-generation sequencing technologies, computational prediction of protein three-dimensional structure is an essential part of modern structural genomics initiatives. Prediction of protein structure through understanding of the theories behind protein sequence-structure relationship, however, remains one of the most challenging problems in contemporary life sciences. Here, we describe MULTICOM, a multi-level combination technique, intended to predict moderate- to high-resolution structure of a protein through a novel approach of combining multiple sources of complementary information derived from the experimentally solved protein structures in the Protein Data Bank. The MULTICOM web server is freely available at http://sysbio.rnet.missouri.edu/multicom_toolbox/.

Assessing the quality of a protein structure model is essential for protein structure prediction. Here, we developed a Support Vector Machine (SVM) method to predict the quality score (GDT-TS score) of a protein structure model from the features extracted from the sequence alignment used to generate the model. We developed a Support Vector Machine (SVM) model quality assessment method, taking either a query-single-template pairwise alignment or a query-multitemplate alignment as input. For the pairwise alignment scheme, the input features fed into the SVM predictor include the normalized e-value of the given alignment, the percentage of identical residue pairs in the alignment, the percentage of residues of the query aligned with those of the template, and the sum of the BLOSUM scores of all aligned residues divided by the length of the aligned positions. Similarly, for the multiple-alignment scheme, the input features include the percentage of the residues of the target sequence aligned with those in one or more templates, the percentage of aligned residues of the target sequence that are the same as that of any one template, the average BLOSUM score of aligned residues and the average Gonnet160 score of aligned residues. A SVM regression predictor was trained on the training data to predict the GDT-TS scores of the models from the input features. The Root Mean Square Error (RMSE) and the Absolute Mean Error (ABS) between predicted and real GDT-TS scores were calculated to evaluate the performance. A five-fold cross validation was applied to select the best parameter values based on the average RMSE and ABS on the five folds. The RMSE and ABS of the optimized SVM predictor on the testing data were close to 0.1. The good performance of the SVM and sequence alignment based predictor indicates that integrating sequence alignment features with a SVM is effective for protein model quality assessment.

Global analysis of gene expression via RNA sequencing was conducted for trisomics for the left arm of chromosome 2 (2L) and compared with the normal genotype. The predominant response of genes on 2L was dosage compensation in that similar expression occurred in the trisomic compared with the diploid control. However, the male and female trisomic/normal expression ratio distributions for 2L genes differed in that females also showed a strong peak of genes with increased expression and males showed a peak of reduced expression relative to the opposite sex. For genes in other autosomal regions, the predominant response to trisomy was reduced expression to the inverse of the altered chromosomal dosage (2/3), but a minor peak of increased expression in females and further reduced expression in males were also found, illustrating a sexual dimorphism for the response to aneuploidy. Moreover, genes with sex-biased expression as revealed by comparing amounts in normal males and females showed responses of greater magnitude to trisomy 2L, suggesting that the genes involved in dosage-sensitive aneuploid effects also influence sex-biased expression. Each autosomal chromosome arm responded to 2L trisomy similarly, but the ratio distributions for X-linked genes were distinct in both sexes, illustrating an X chromosome-specific response to aneuploidy.

Dosage compensation, the equalized X chromosome gene expression between males and females in Drosophila, has also been found in triple X metafemales. Inverse dosage effects, produced by genomic imbalance, are believed to account for this modulated expression, but they have not been studied on a global level. Here, we show a global expression comparison of metafemales (XXX; AA) with normal females (XX; AA) with high-throughput RNA-sequencing. We found that the majority of the X-linked genes in metafemales exhibit dosage compensation with an expression level similar to that of normal diploid females. In parallel, most of the autosomal genes were expressed at about two-thirds the level of normal females, the ratio of inverse dosage effects produced by the extra X chromosome. Both compensation and inverse effects were further confirmed by combination of X-linked and autosomally located miniwhite reporter genes in metafemales and relative quantitative PCR of selected genes. These data provide evidence for an inverse dosage component to X chromosome compensation.

This study aimed at developing a novel lipid nanoemulsion formulation of doxorubicin (DOX) which is feasible for scale-up production, exhibits good parenteral acceptability, and further improves the therapeutic index of the drug. Oleic acid was used to form ionic complex with DOX in order to enhance its lipophilicity. The lipid nanoemulsions loaded with doxorubicin-oleic acid complex (DOX-OA-LNs) were prepared using a simple high-pressure homogenization method and fully characterized from physicochemical and in vitro release standpoint. Afterwards, the DOX-OA-LNs and free DOX were compared with respect to their in vitro cellular uptake and cytotoxicity, and their in vivo pharmacokinetics and biodistribution behavior in mice were also investigated. The obtained DOX-OA-LNs could achieve high encapsulation efficiency of 93.7 +/- 1.2% under optimal conditions. The in vitro release behavior displayed biphasic drug release pattern with rapid release at the initial stage and prolonged release afterwards. The DOX-OA-LNs exhibited higher growth inhibitory effect than free DOX by MTT assay. Flow cytometry and confocal microscopy studies showed that the cellular uptake of free DOX and DOX-OA-LNs were comparable. Pharmacokinetics and in vivo distribution studies in mice showed that DOX-OA-LNs demonstrated significantly higher DOX level in blood and longer circulation time than free DOX. Moreover, DOX-OA-LNs significantly decreased DOX concentration in heart, lung and kidney. These results suggested that DOX-OA-LNs could be a promising formulation for the delivery of DOX in tumor chemotherapy.

A series of beta-formyl-BODIPYs 2 were synthesized in high yields from tetramethyl-BODIPYs 1 via the Vilsmeier-Haack reaction and were further functionalized using a Knoevenagel condensation to generate novel BODIPYs 3 and 4.