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Three covalent organic polymers (COPs) were successfully fabricated by room-temperature solvent-free mechanochemical grinding method between 1,3,5-triformylphloroglucinol (TP) and p-phenyl enediamine (COP1), benzidine (COP2), 4, 4″-diamino-p-terphenyl (COP3), and followed by coprecipitation on the surface of Fe3O4 nanoparticles to form three corresponding magnetic Tp-series COPs. The fabricated magnetic COPs were evaluated and then applied for the extraction of phthalate esters from food samples before gas chromatography-tandem spectrometry analysis. Magnetic COP2 exhibited the highest extraction efficiency, which can be attributed to its larger pore size, and its strong hydrophobic and π-π interactions with phthalate esters. The method possessed good linearity (10–1000 μg·kg−1), high sensitivity (0.29–2.59 µg·kg−1 for LODs and 0.97–8.63 µg·kg−1 for LOQs), and satisfactory recoveries (70.2–108.1%) with relative standard deviations lower than 5.2%. This method has potentials for high efficient separation/preconcentration of hydrophobic phthalate esters from foods.

Cotton fibers are the main raw materials of the textile industry. Exogenous superior fiber genes have been introduced into upland cotton to develop high-yield cultivars with excellent fiber quality. We used a single chromosomal segment on the chromosome A07 substitution line SL7, with high fiber strength, to investigate the molecular mechanism underlying its fiber quality. RNA-seq and KEGG analysis showed that 70 differentially expressed genes were enriched in plant hormone transduction pathways, including auxin, ethylene and abscisic acid, in fibers at 10 days post-anthesis (DPA). Among these, fiber-development related transcription factors MYB and NAC, including Gh_A11G0981 (MYB108), Gh_A03G0887 (NAC029), and Gh_A08G1691 (NAC021), were significantly upregulated in SL7, as were numerous cellulose synthase-like (CSL) genes involved in non-cellulose polysaccharide and cell wall synthesis. The hemicellulose content of SL7 was significantly higher than that of L22, an upland cotton cultivar. These results suggest that key genes in the introgressed chromosomal segment of SL7 regulate the expression of transcription-factor genes via hormone-transduction pathways, thereby inducing the expression of genes involved in secondary wall synthesis and ultimately improving fiber quality. This study has shed light on the molecular mechanism of fiber development and will contribute to the improvement of fiber quality of upland cotton by molecular breeding. Keywords: Cotton fiber quality, Single-fragment substitution line, RNA-seq, Hormone transduction pathway, Transcription factor

This paper proposes a novel pixel interval down-sampling network (PID-Net) for dense tiny object (yeast cells) counting tasks with higher accuracy. The PID-Net is an end-to-end convolutional neural network (CNN) model with an encoder–decoder architecture. The pixel interval down-sampling operations are concatenated with max-pooling operations to combine the sparse and dense features. This addresses the limitation of contour conglutination of dense objects while counting. The evaluation was conducted using classical segmentation metrics (the Dice, Jaccard and Hausdorff distance) as well as counting metrics. The experimental results show that the proposed PID-Net had the best performance and potential for dense tiny object counting tasks, which achieved 96.97% counting accuracy on the dataset with 2448 yeast cell images. By comparing with the state-of-the-art approaches, such as Attention U-Net, Swin U-Net and Trans U-Net, the proposed PID-Net can segment dense tiny objects with clearer boundaries and fewer incorrect debris, which shows the great potential of PID-Net in the task of accurate counting.

Background The circadian clock not only participates in regulating various stages of plant growth, development and metabolism, but confers plant environmental adaptability to stress such as drought. Pseudo-Response Regulators (PRRs) are important component of the central oscillator (the core of circadian clock) and play a significant role in plant photoperiod pathway. However, no systematical study about this gene family has been performed in cotton. Methods PRR genes were identified in diploid and tetraploid cotton using bioinformatics methods to investigate their homology, duplication and evolution relationship. Differential gene expression, KEGG enrichment analysis and qRT-PCR were conducted to analyze PRR gene expression patterns under diurnal changes and their response to drought stress. Results A total of 44 PRR family members were identified in four Gossypium species, with 16 in G. hirsutum, 10 in G. raimondii, and nine in G. barbadense as well as in G. arboreum. Phylogenetic analysis indicated that PRR proteins were divided into five subfamilies and whole genome duplication or segmental duplication contributed to the expansion of Gossypium PRR gene family. Gene structure analysis revealed that members in the same clade are similar, and multiple cis-elements related to light and drought stress response were enriched in the promoters of GhPRR genes. qRT-PCR results showed that GhPRR genes transcripts presented four expression peaks (6 h, 9 h, 12 h, 15 h) during 24 h and form obvious rhythmic expression trend. Transcriptome data with PEG treatment, along with qRT-PCR verification suggested that members of clade III (GhPRR5a, b, d) and clade V (GhPRR3a and GhPRR3c) may be involved in drought response. This study provides an insight into understanding the function of PRR genes in circadian rhythm and in response to drought stress in cotton.

BACKGROUND & AIMS: Symptoms of constipation are extremely common, especially in the elderly. The present study aim to identify an efficacious treatment strategy for constipation by evaluating the secretion-promoting and laxative effect of a herbal compound, naringenin, on intestinal epithelial anion secretion and a rat constipation model, respectively. METHODS/PRINCIPAL FINDINGS: In isolated rat colonic crypts, mucosal addition of naringenin (100 microM) elicited a concentration-dependent and sustained increase in the short-circuit current (I(SC)), which could be inhibited in Cl- free solution or by bumetanide and DPC (diphenylamine-2-carboxylic acid), but not by DIDS (4, 4'- diisothiocyanatostilbene-2, 2'-disulfonic acid). Naringenin could increase intracellular cAMP content and PKA activity, consisted with that MDL-12330A (N-(Cis-2-phenyl-cyclopentyl) azacyclotridecan-2-imine-hydrochloride) pretreatment reduced the naringenin-induced I(SC). In addition, significant inhibition of the naringenin-induced I(SC) by quinidine indicated that basolateral K+ channels were involved in maintaining this cAMP-dependent Cl- secretion. Naringenin-evoked whole cell current which exhibited a linear I-V relationship and time-and voltage- independent characteristics was inhibited by DPC, indicating that the cAMP activated Cl- conductance most likely CFTR (cystic fibrosis transmembrane conductance regulator) was involved. In rat constipation model, administration of naringenin restored the level of fecal output, water content and mucus secretion compared to loperamide-administrated group. CONCLUSIONS: Taken together, our data suggest that naringenin could stimulate Cl- secretion in colonic epithelium via a signaling pathway involving cAMP and PKA, hence provide an osmotic force for subsequent colonic fluid secretion by which the laxative effect observed in the rat constipation model. Naringenin appears to be a novel alternative treatment strategy for constipation.

Surface fractures have a great impact on ice shelf stability in Antarctica and can be considered precursors of ice shelf calving. However, our understanding of the spatial distribution and temporal evolution of surface fractures on the Antarctic ice shelf is limited. In this study, a ResUNet model was implemented on the Moderate Resolution Imaging Spectroradiometer (MODIS)-based Mosaic of Antarctica (MOA) to identify the spatial distribution of Antarctic ice shelf surface fractures in 2004, 2009, and 2014. The accuracy of identification had an F1 value of 0.771. Our model identified 44744.59$\; \pm \;$2619.61 km² of surface fractures in 2004, 43737.15$\; \pm \;$2644.60 km² in 2009, and 42978.67 $\pm \;$2639.33 km² in 2014. The reduction is primarily attributed to the variation in surface fractures within 20 km of the ice front, paratactically in the Amundsen and Wilkes sectors. Ice shelves in the Amundsen sector typically have a widespread distribution of surface fractures, with particularly high concentrations found in the Thwaites Ice Shelf, Crosson Ice Shelf and Getz Ice Shelf. The Brunt Ice Shelf also exhibits numerous surface fractures. This study provides comprehensive and detailed information about surface fractures on Antarctic ice shelves, carrying implications for evaluating ice shelf vulnerability.

This study investigated whether the relationships of personality with safety compliance and safety participation remains significant when safety-specific transformational leadership is supplied by supervisors. It also tested the moderating role of this leadership in the personality-safety behavior relationship. One hundred twenty workers completed the Big Five personality test and graded their supervisors' leadership, and the workers' safety behavior was assessed by the supervisors. The results showed that conscientiousness was related positively with safety compliance. Contrary to our theorizing, agreeableness was related negatively with safety compliance. Leadership always positively related to safety compliance and participation, and it also attenuated the relationships of conscientiousness and agreeableness with safety compliance. This enhances the importance of considering safety leadership as an antecedent and intervention of employee safety behavior. However, conscientiousness and agreeableness remained related with safety compliance when safety leadership was considered simultaneously. These findings expand the limited research on the personality-safety behavior relationship in the construction field. Evaluating conscientiousness and agreeableness prior to recruitment can enable employers proactively to curtail unacceptable safety transgressions. Enhancing supervisors' safety leadership helps to prevent employees from performing safety-related actions that are subject to individual dispositions. [ABSTRACT FROM AUTHOR]

The continuous development of magnetic bearing in areas of aerospace, military, turbine power generation and flywheel energy storage has raised higher requirement for the reliability of magnetic bearing system. However, the integrated armco iron structure adopted by traditional concentric axial redundant magnetic bearing stator causes more eddy current loss and temperature rise when working and is not reliable. For the purpose of reducing eddy current loss and improving the reliability of magnetic bearing, this paper proposes a laminated core type axial redundant magnetic bearing. The comparison of dual-ring axial redundant magnetic bearing and laminated core type axial redundant magnetic bearing regarding their carrying capacity and temperature rise performance showed that the latter was better in an obvious way. [ABSTRACT FROM AUTHOR]

TMT (trimethyltin chloride), an organotin, is ubiquitous in the environment. The consumption of contaminated food may cause exposure of the human diet to this toxic compound. The present study was to investigate the effects of TMT on the regulation of ion transport across the rat distal colon. The rat colonic mucosa was mounted in Ussing chambers. The effects of TMT were assessed using the Isc (short-circuit current). Both apical and basolateral TMT induced, dose-dependently, an increase in Isc, which was due to a stimulation of Cl- secretion as measured using ion substitution experiments and pharmacological manoeuvres. The secretion was also inhibited by several K+ channel blockers administrated at the basolateral side. When the apical side was permeabilized by nystatin, the TMT-induced K+ conductance was effectively blocked by tetrapentylammonium, a Ca2+-sensitive K+ channel blocker. The response of TMT was sensitive to the basolateral Ca2+ and the intracellular Ca2+ store, which could be disclosed by applying the inhibitors of ryanodine receptors and inositol 1,4,5-trisphosphate receptors. In conclusion, TMT led to Cl- secretion, which was essentially regulated by basolateral Ca2+-sensitive K+ channels. These results suggest the importance of K+ channels in the toxicity hazard of TMT. [ABSTRACT FROM AUTHOR]

Purpose. Acute cholangitis (AC) is a widespread acute inflammatory disease and the main cause of septic shock, which has a high death rate in hospitals. At present, the prediction models for short-term mortality of AC patients are still not ideal. We aimed at developing a new model that could forecast the short-term mortality rate of AC patients. Methods. Data were extracted from the Medical Information Mart for Intensive Care IV version 2.0 (MIMIC-IV v2.0). There were a total of 506 cases of AC patients that were included. Patients were given a 7 : 3 split between the training set and the validation set after being randomly assigned to one of the groups. Multivariate logistic regression was used to create an AC patient predictive nomogram for 30-day mortality. The overall efficacy of the model is evaluated using the area under the receiver operating characteristic curve (AUC), the calibration curve, the net reclassification improvement (NRI), the integrated discrimination improvement (IDI), and a decision curve analysis (DCA). Results. Out of 506 patients, 14.0% (71 patients) died. The training cohort had 354 patients, and the validation cohort had 152 patients. GCS, SPO2, albumin, AST/ALT, glucose, potassium, PTT, and peripheral vascular disease were the independent risk factors according to the multivariate analysis results. The newly established nomogram had better prediction performance than other common scoring systems (such as SOFA, OASIS, and SAPS II). For two cohorts, the calibration curve demonstrated coherence between the nomogram and the ideal observation P > 0.05. The clinical utility of the nomogram in both sets was revealed by decision curve analysis. Conclusion. The novel prognostic model was effective in forecasting the 30-day mortality rate for acute cholangitis patients.