With the exponential growth in the application of the HILIC technique, there has been a significant progress in understanding the fundamental aspects of hydrophilic interaction chromatography. The ...experimental studies tend to be more extensive in terms of the number of stationary phases investigated and the number of probe compounds employed in comparison with the earlier studies; and more theoretical studies in quantitative structure retention relationship (QSRR) and molecular dynamics simulations have also been published and provide molecular-level insights into the retention mechanism. This review focuses on the recent progress in understanding the retention mechanism, retention models, selectivity, and the kinetic performance of HILIC. A better understanding of these fundamental aspects will undoubtedly facilitate more applications of this chromatographic technique in a wider range of fields.
In the emerging Internet of Things, stretchable antennas can facilitate wireless communication between wearable and mobile electronic devices around the body. The proliferation of wireless devices ...transmitting near the human body also raises interference and safety concerns that demand stretchable materials capable of shielding electromagnetic interference (EMI). Here, an ultrastretchable conductor is fabricated by depositing a crumple‐textured coating composed of 2D Ti3C2Tx nanosheets (MXene) and single‐walled carbon nanotubes (SWNTs) onto latex, which can be fashioned into high‐performance wearable antennas and EMI shields. The resulting MXene‐SWNT (S‐MXene)/latex devices are able to sustain up to an 800% areal strain and exhibit strain‐insensitive resistance profiles during a 500‐cycle fatigue test. A single layer of stretchable S‐MXene conductors demonstrate a strain‐invariant EMI shielding performance of ≈30 dB up to 800% areal strain, and the shielding performance is further improved to ≈47 and ≈52 dB by stacking 5 and 10 layers of S‐MXene conductors, respectively. Additionally, a stretchable S‐MXene dipole antenna is fabricated, which can be uniaxially stretched to 150% with unaffected reflected power <0.1%. By integrating S‐MXene EMI shields with stretchable S‐MXene antennas, a wearable wireless system is finally demonstrated that provides mechanically stable wireless transmission while attenuating EM absorption by the human body.
2D titanium carbide–based ultrastretchable conductors are fabricated by harnessing the surface instability of pre‐stretched latex, showing strain‐invariant performance in stretchable electromagnetic interference (EMI) shields and wearable wireless communicators, respectively. Finally, a wearable antenna with on‐site EM protection for the human body is demonstrated, which exhibits mechanically stable and efficient wireless communication and shielding performance.
Apoptosis and autophagy are dynamic processes that determine the fate of cells. Vitamin D receptor (VDR) deficiency in the intestine leads to abnormal Paneth cells and impaired autophagy function. ...Here, we will elucidate the mechanisms of the intestinal epithelial VDR regulation of autophagy and apoptosis. We used in vivo VDRlox and VDRΔIEC mice and ex vivo organoids generated from small intestine and colon tissues. We found that VDR deficiency induced more apoptotic cells and significantly increased cell death in the small intestine and colon of VDRΔIEC mice. The proapoptotic protein B‐cell lymphoma 2 (BCL‐2) associated X protein (Bax) was enhanced, whereas autophagy related 16 like 1 (ATG16L1) and Beclin‐1 were decreased in the intestines of VDRΔIEC mice. Apoptosis induced by Bax reduced autophagy by decreasing Beclin‐1. Physical interactions between Beclin‐1 and Bcl‐2 were increased in the VDR‐deficient epithelia from mice. The growth of VDRΔIEC organoids was significantly slower with fewer Paneth cells than that of VDR+/+ organoids. The expression levels of Beclin‐1 and lysozyme were decreased in VDRΔIEC organoids. Bacterial endotoxin levels were high in the serum from VDRΔIEC mice and made mice susceptible to colitis. In the organoids and colitis IL‐10‐/‐ mice, vitamin D3 treatment increased VDR and ATG16L1 protein expression levels, which activated autophagic responses. In summary, intestinal epithelial VDR regulates autophagy and apoptosis through ATG16L1 and Beclin‐1. Our studies provide fundamental insights into the tissue‐specific function of VDR in modulating the balance between autophagy and apoptosis.—Lu, R., Zhang, Y.‐G., Xia, Y., Sun, J. Imbalance of autophagy and apoptosis in intestinal epithelium lacking the vitamin D receptor. FASEB J. 33, 11845‐11856 (2019). www.fasebj.org
An efficient protocol for the synthesis of 3‐aminoquinoxalinones via the electrochemical dehydrogenative C‐3 amination of quinoxalin‐2(1H)‐ones was developed. With aliphatic amines and azoles as the ...nitrogen sources, a series of 3‐aminoquinoxalinones was obtained in up to 99% yield. This direct electrolytic method avoids the use of transition metals and external oxidants, and represents an appealing alternative for the synthesis of 3‐aminoquinoxalinones.
The in vitro analysis of bacterial–epithelial interactions in the intestine has been hampered by a lack of suitable intestinal epithelium culture systems. Here, we report a new experimental model ...using an organoid culture system to study pathophysiology of bacterial–epithelial interactions post Salmonella infection. Using crypt‐derived mouse intestinal organoids, we were able to visualize the invasiveness of Salmonella and the morphologic changes of the organoids. Importantly, we reported bacteria‐induced disruption of epithelial tight junctions in the infected organoids. In addition, we showed the inflammatory responses through activation of the NF‐κB pathway in the organoids. Moreover, our western blot, PCR, and immunofluorescence data demonstrated that stem cell markers (Lgr5 and Bmi1) were significantly decreased by Salmonella infection (determined using GFP‐labeled Lgr5 organoids). For the first time, we created a model system that recapitulated a number of observations from in vivo studies of the Salmonella‐infected intestine, including bacterial invasion, altered tight junctions, inflammatory responses, and decreased stem cells. We have demonstrated that the Salmonella‐infected organoid culture system is a new experimental model suitable for studying host–bacterial interactions.
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Using stem cell‐derived intestinal organoids, we were able to visualize the invasiveness of Salmonella, morphologic changes of the organoids, and showed the inflammatory responses through activating the NF‐κB pathway in the organoids. Moreover, we show that stem cell markers (Lgr5 and Bmi1) were decreased by Salmonella infection. Taken together, the model system we have recreated recapitulates for the first time a number of observations from in vivo studies of Salmonella‐infected gut. Thus, Salmonella‐infected organoid culture system is a new experimental model suitable for studying host–bacterial interactions.
Fall accidents are significant threats to the health and life of older people. When a millimetre-wave (mmWave) frequency modulated continuous wave (FMCW) radar is used for fall detection, the ...selected features for further classification can determine the detection performance. In this paper, a line kernel convolutional neural network (LKCNN) is proposed to process the baseband data directly to detect fall motions. This method utilizes the characteristic of a convolutional neural network (CNN) that it can learn to extract useful features during the training process. A data sample generation method is also proposed to generate multiple samples for the training process by utilizing the multiple receiving channels and sufficiently small pulse repetition time (PRT). The experiment results show that the proposed method can detect fall motions with high accuracy, sensitivity and specificity with fewer network parameters and less computation cost, which is meaningful in realizing an all-time indoor fall detection system.
The SARS-CoV-2-infected disease (COVID-19) outbreak is a major threat to human beings. Previous studies mainly focused on Wuhan and typical symptoms. We analysed 74 confirmed COVID-19 cases with GI ...symptoms in the Zhejiang province to determine epidemiological, clinical and virological characteristics.
COVID-19 hospital patients were admitted in the Zhejiang province from 17 January 2020 to 8 February 2020. Epidemiological, demographic, clinical, laboratory, management and outcome data of patients with GI symptoms were analysed using multivariate analysis for risk of severe/critical type. Bioinformatics were used to analyse features of SARS-CoV-2 from Zhejiang province.
Among enrolled 651 patients, 74 (11.4%) presented with at least one GI symptom (nausea, vomiting or diarrhoea), average age of 46.14 years, 4-day incubation period and 10.8% had pre-existing liver disease. Of patients with COVID-19 with GI symptoms, 17 (22.97%) and 23 (31.08%) had severe/critical types and family clustering, respectively, significantly higher than those without GI symptoms, 47 (8.14%) and 118 (20.45%). Of patients with COVID-19 with GI symptoms, 29 (39.19%), 23 (31.08%), 8 (10.81%) and 16 (21.62%) had significantly higher rates of fever >38.5°C, fatigue, shortness of breath and headache, respectively. Low-dose glucocorticoids and antibiotics were administered to 14.86% and 41.89% of patients, respectively. Sputum production and increased lactate dehydrogenase/glucose levels were risk factors for severe/critical type. Bioinformatics showed sequence mutation of SARS-CoV-2 with m
A methylation and changed binding capacity with ACE2.
We report COVID-19 cases with GI symptoms with novel features outside Wuhan. Attention to patients with COVID-19 with non-classic symptoms should increase to protect health providers.
This article presents a multibeam dual circularly polarized (CP) Luneburg lens (LL) antenna based on quasi-icosahedron (QICO) models. The lens is sliced into multiple shells and each shell comprises ...of several triangular unit cells, and then the permittivity variation is achieved by manipulating the wall thickness of each triangular unit cells after the QICO discretization. Such a QICO model is firstly proposed to be used in LL design, which not only makes the lens mechanically robust and manufacturing-friendly (no support is needed in the processing) but also enables the antenna to be polarization insensitive and thus can sustain CP beams very well. A wideband ridged waveguide feed is selected to initiate left-handed CP (LHCP) and right-handed CP (RHCP) beams simultaneously. To prove the concept, a prototype was fabricated using 3-D-printing (3DP) technologies. The measurement results reveal an overlapped bandwidth of 33.1% (26.5-37 GHz) in terms of reflection coefficients lower than −10 dB and axial ratios smaller than 3 dB. Five LHCP and five RHCP beams with gains of 19-21.2 dBic and couplings lower than −20 dB are also demonstrated.
Additional resonances are often introduced in an inverted-F antenna (IFA) by modifying the "F" structure, which typically makes the antenna both complex and bulky. To mitigate this problem, novel ...dual-/tri-band conformal capsule antennas with simple configuration are proposed in this paper by modifying the ground of the IFA and shifting the feed point. With these modifications, the IFA is miniaturized, and yet it is able to simultaneously cover the MedRadio band (401-406 MHz) and ISM bands (902-928 MHz and/or 2.4-2.5 GHz). The resulting configurations remain simple and compact despite the modifications, which is very desirable for conformal capsule type of applications. Furthermore, the impedance matching characteristics of the proposed IFAs remain stable even when a battery is added inside the capsule and the size or the position of the battery is modified. Moreover, the impedance matching of the antenna continues to remain stable even as its surrounding environment is changed. The operating principle of the proposed dual-/tri-band IFAs is discussed in detail and parametric study is carried out to investigate the characteristics of the proposed antennas. The results of this paper are expected to be helpful for designing multiband antennas in the future.
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