Non-equilibrium behaviour in coacervate-based protocells under electric-field-induced excitation

Although numerous strategies are now available to generate rudimentary forms of synthetic cell-like entities, minimal progress has been made in the sustained excitation of artificial protocells under non-equilibrium conditions. Here we demonstrate that the electric field energization of coacervate microdroplets comprising polylysine and short single strands of DNA generates membrane-free protocells with complex, dynamical behaviours. By confining the droplets within a microfluidic channel and applying a range of electric field strengths, we produce protocells that exhibit repetitive cycles of vacuolarization, dynamical fluctuations in size and shape, chaotic growth and fusion, spontaneous ejection and sequestration of matter, directional capture of solute molecules, and pulsed enhancement of enzyme cascade reactions. Our results highlight new opportunities for the study of non-equilibrium phenomena in synthetic protocells, provide a strategy for inducing complex behaviour in electrostatically assembled soft matter microsystems and illustrate how dynamical properties can be activated and sustained in microcompartmentalized media.</p

Comparison of bloodstream and non-bloodstream infections caused by carbapenem-resistant Klebsiella pneumoniae in the intensive care unit: a 9-year respective study

BackgroundBloodstream infections (BSIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) have received much attention. However, few studies have identified risk factors for CRKP BSIs in comparison to CRKP non-bloodstream infections (non-BSIs). This study aimed to compare the epidemiology, risk factors, and outcomes of CRKP BSIs and CRKP non-BSIs.MethodsWe conducted a retrospective study of patients infected with CRKP in the ICU from January 2012 to December 2020. Clinical characteristics and outcomes were compared between CRKP BSIs and CRKP non-BSIs. Predictors associated with 28-day all-cause mortality in CRKP-infected patients were also evaluated.Results326 patients infected with CRKP were enrolled, including 96 patients with CRKP BSIs and 230 with CRKP non-BSIs. The rates of CRKP BSIs in CRKP infections were generally raised from 2012 (12.50%) to 2020 (45.76%). Multivariate logistic analysis indicated that the use of carbapenems within the prior 90 days was an independent risk factor for CRKP BSIs (p = 0.019). Compared to CRKP non-BSIs, CRKP isolates in the CRKP BSI group were found to be non-susceptible to more tested carbapenems (p = 0.001). Moreover, the CRKP BSI group exhibited a higher mortality rate (p = 0.036). The non-susceptibility of CRKP isolates to more tested carbapenems (p = 0.025), a high SOFA score (p = 0.000), and the use of antifungal drugs within the prior 90 days (p = 0.018) were significant factors for 28-day all-cause mortality in CRKP-infected patients.ConclusionThe proportion of CRKP BSI increased progressively in CRKP-infected patients over 9 years. The use of carbapenems within the prior 90 days was an independent risk factor for the development of CRKP BSIs. The non-susceptibility of CRKP isolates to more tested carbapenems and a higher mortality rate were found in the CRKP BSI group

MicroRNA-275 and its target vitellogenin-2 are crucial in ovary development and blood digestion of Haemaphysalis longicornis

Background: The hard tick Haemaphysalis longicornis is widely distributed in eastern Asia, New Zealand and Australia and is considered the major vector of Theileria and Babesia, harmful parasites to humans and animals. Female ticks need successful blood meals to complete the life-cycle. Therefore, elucidation of the underlying molecular mechanisms of H. longicornis development and reproduction is considered important for developing control strategies against the tick and tick-borne pathogens. Methods: Luciferase assays were used to identify the targets of micro RNA miR-275 in vitro. RNAi of Vitellogenin (Vg) was used in phenotype rescue experiments of ticks with miR-275 inhibition, and these analyses were used to identify the authentic target of miR-275 in vivo. The expression of miR-275 in different tissues and developmental stages of ticks was assessed by real-time PCR. To elucidate the functions of miR-275 in female ticks, we injected a miR-275 antagomir into female ticks and observed the phenotypic changes. Statistical analyses were performed with GraphPad5 using Student’s t-test. Results: In this study, we identified Vg-2 as an authentic target of miR-275 both in vitro and in vivo by luciferase assays and phenotype rescue experiments. miR-275 plays the regulatory role in a tissue-specific manner and differentially in developmental stages. Silencing of miR-275 resulted in blood digestion problems, substantially impaired ovary development and significantly reduced egg mass (P < 0.0001). Furthermore, RNAi silencing of Vg-2 not only impacted the blood meal uptake (P < 0.05) but also the egg mass (P < 0.05). Significant rescue was observed in miR-275 knockout ticks when RNAi was applied to Vg-2. Conclusion: To our knowledge, this study is the first demonstration that miR-275 targets Vg-2 in H. longicornis and regulates the functions of blood digestion and ovary development. These findings improve the molecular understanding of tick development and reproduction

Semi-supervised clustering with deep metric learning and graph embedding

As a common technology in social network, clustering has attracted lots of research interest due to its high performance, and many clustering methods have been presented. The most of existing clustering methods are based on unsupervised learning. In fact, we usually can obtain some/few labeled samples in real applications. Recently, several semi-supervised clustering methods have been proposed, while there is still much space for improvement. In this paper, we aim to tackle two research questions in the process of semi-supervised clustering: (i) How to learn more discriminative feature representations to boost the process of the clustering; (ii) How to effectively make use of both the labeled and unlabeled data to enhance the performance of clustering. To address these two issues, we propose a novel semi-supervised clustering approach based on deep metric learning (SCDML) which leverages deep metric learning and semi-supervised learning effectively in a novel way. To make the extracted features of the contribution of data more representative and the label propagation network more suitable for real applications, we further improve our approach by adopting triplet loss in deep metric learning network and combining bedding with label propagation strategy to dynamically update the unlabeled to labeled data, which is named as semi-supervised clustering with deep metric learning and graph embedding (SCDMLGE). SCDMLGE enhances the robustness of metric learning network and promotes the accuracy of clustering. Substantial experimental results on Mnist, CIFAR-10, YaleB, and 20-Newsgroups benchmarks demonstrate the high effectiveness of our proposed approaches

Identification of Acoustic Characteristic Parameters and Improvement of Sound Absorption Performance for Porous Metal

Porous metal is widely used in the fields of sound absorption and noise reduction, and it is a critical procedure to identify acoustic characteristic parameters and to improve sound absorption performances. Based on the constructed theoretical sound absorption model and experimental data, acoustic characteristic parameters of the porous metal were identified through the cuckoo search identification algorithm, and their reliabilities were certified through comparing with these labeled parameters and further experimental validation. By adding the microperforated metal panel in front of the porous metal, a composite sound-absorbing structure was formed, which aimed to improve the sound absorption performance of the original porous metal by optimizing the parameters. Finite element simulation and a standing wave tube measurement were conducted to validate the effectiveness and practicability of the optimal composite sound-absorbing structure. Consistencies among theoretical predictions, simulation results, and experimental data proved the effectiveness of the identification and optimization method. When the target frequency ranges were 100&ndash;1000 Hz, 100&ndash;2000 Hz, 100&ndash;3000 Hz, and 100&ndash;4000 Hz. Actual average sound absorption coefficients of the optimal composite structures were 0.5154, 0.6369, 0.6770, and 0.7378, respectively, which exhibited the obvious improvements with a tiny increase in the occupied space and a small addition in weight

Clinical characteristics of carbapenem-resistant Klebsiella pneumoniae infection/colonisation in the intensive care unit: a 9-year retrospective study

Objectives Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection/colonisation has been reported in hospitals. The clinical characteristics of CRKP infection/colonisation in the intensive care unit (ICU) have received little attention. This study aims to investigate the epidemiology and extent of K. pneumoniae (KP) resistance to carbapenems, the sources of CRKP patients and CRKP isolates, and the risk factors for CRKP infection/colonisation.Design Retrospective single-centre study.Data source Clinical data were obtained from electronic medical records.Participants Patients isolated with KP in the ICU from January 2012 to December 2020.Main outcome measures The prevalence and changing trend of CRKP were determined. The extent of KP isolates resistance to carbapenems, the specimen types of KP isolates, and the sources of CRKP patients and CRKP isolates were all examined. The risk factors for CRKP infection/colonisation were also assessed.Results The rate of CRKP in KP isolates raised from 11.11% in 2012 to 48.92% in 2020. CRKP isolates were detected in one site in 266 patients (70.56%). The percentage of CRKP isolates not susceptible to imipenem increased from 42.86% in 2012 to 98.53% in 2020. The percentage of CRKP patients from general wards in our hospital and other hospitals gradually converged in 2020 (47.06% vs 52.94%). CRKP isolates were mainly acquired in our ICU (59.68%). Younger age (p=0.018), previous admission (p=0.018), previous ICU stay (p=0.008), prior use of surgical drainage (p=0.012) and gastric tube (p=0.001), and use of carbapenems (p=0.000), tigecycline (p=0.005), β-lactams/β-lactamase inhibitors (p=0.000), fluoroquinolones (p=0.033), and antifungal drugs (p=0.011) within the prior 3 months were independent risk factors for CRKP infection/colonisation.Conclusions Overall, the rate of KP isolates resistance to carbapenems increased, and the severity of this resistance significantly increased. Intensive and local infection/colonisation control measures are necessary for ICU patients, especially those with risk factors for CRKP infection/colonisation

CEBPG suppresses ferroptosis through transcriptional control of SLC7A11 in ovarian cancer

Abstract Background Ovarian cancer (OC) has high mortality and poor prognosis for lacking of specific biomarkers and typical clinical symptoms in the early stage. CEBPG is an important regulator in tumor development, yet it is unclear exactly how it contributes to the progression of OC. Methods TCGA and tissue microarrays with immunohistochemical staining (IHC) were used to examine CEBPG expression in OC. A variety of in vitro assays were conducted, including colony formation, proliferation, migration, and invasion. The orthotopic OC mouse model was established for in vivo studies. Ferroptosis was detected by observing mitochondrial changes with electron microscopy, detecting ROS expression, and detecting cell sensitivity to drugs by CCK8 assay. The interaction between CEBPG and SLC7A11 was confirmed by CUT&Tag and dual luciferase reporter assays. Results A significantly higher expression level of CEBPG in OC when compared with benign tissues of ovary, and that high CEBPG expression level was also tightly associated with poor prognosis of patients diagnosed with OC, as determined by analysis of datasets and patient samples. Conversely, knockdown of CEBPG inhibited OC progression using experiments of OC cell lines and in vivo orthotopic OC-bearing mouse model. Importantly, CEBPG was identified as a new participator mediating ferroptosis evasion in OC cells using RNA-sequencing, which could contribute to OC progression. The CUT&Tag and dua luciferase reporter assays further revealed the inner mechanism that CEBPG regulated OC cell ferroptosis through transcriptional control of SLC7A11. Conclusions Our findings established CEBPG as a novel transcriptional regulator of OC ferroptosis, with potential value in predicting clinical outcomes and as a therapeutic candidate

Influences of Compression Ratios on Sound Absorption Performance of Porous Nickel–Iron Alloy

The improvement of sound absorption performance of porous metal is a focus of research in the field of noise reduction. Influences of compression ratios on sound absorption performance of a porous nickel–iron (Ni–Fe) alloy were investigated. The samples were compressed with ratios from 10% to 80% at an interval of 10%. Based on the standing wave method, sound absorption coefficients of compressed samples with different thicknesses were obtained. It could be found that with the same compression ratio, sound absorption performance was improved with the increase of thickness. Based on the modified Johnson–Allard model with a correction factor, the sound absorption coefficient of the porous Ni–Fe with a thickness of 20 mm for different compression ratios was derived, whose aim was to quantificationally analyze influences of the compression ratio. The results indicated that the sample with a compression ratio of 70% exhibited optimal sound absorption performance, and its average sound absorption coefficient reached 88.97% in a frequency range of 1000–6000 Hz. Meanwhile, the section morphologies of compressed samples were investigated by a scanning electron microscope, which studied the sound absorption performance by analyzing structures of the porous Ni–Fe samples with different compression ratios. The obtained achievements will promote the application of the porous Ni–Fe alloy in the field of acoustics

Semi-supervised Clustering with Deep Metric Learning

Semi-supervised clustering has attracted lots of reserach interest due to its broad applications, and many methods have been presented. However there is still much space for improvement, (1) How to learn more discriminative feature representations to assist the traditional clustering methods; (2) How to make use of both the labeled and unlabelled data simultaneously and effectively during the process of clustering. To address these issues, we propose a novel semi-supervised clustering based on deep metric learning, namely SSCDML. By leveraging deep metric learning and semi-supervised learning effectively in a novel way, SSCDML dynamically update the unlabelled to labeled data through the limited labeled samples and obtain more meaningful data features, which make the classifier model more robust and the clustering results more accurate. Experimental results on Mnist, YaleB, and 20 Newsgroups databases demonstrate the high effectiveness of our proposed approach

Recovery of Silver from Wastewater Using a New Magnetic Photocatalytic Ion-Imprinted Polymer

A novel magnetic, photocatalytic, and Ag­(I)-imprinted thiol-functionalized polymer (Fe₃O₄@SiO₂@TiO₂-IIP) was prepared as functionalized IIP for selective removal and recycling of Ag⁺ ions from actual wastewater. The material used in this study exhibited a promising silver saturation adsorption capacity of 35.475 mg/g under the optimum pH of 6 within 80 min. The specific Ag⁺ ion adsorption property of the material was excellently offered by the Ag­(I)-imprinted thiol-functionalized polymer. The selectivity separation factors for Ag⁺ with respect to Li⁺, Co²⁺, Cu²⁺, and Ni²⁺ are 10.626, 27.829, 13.276, and 68.109, respectively. In the presence of TiO₂ and methanol used as the sacrificial agent (methanol/water 15:40), the adsorbed Ag­(I) can be reduced to Ag(0) and then separated from the imprinted polymers after the ultrasound. The reduction rate is 0.00566 min^–1 based on a pseudo-first-order kinetic model. The retained adsorption capacity of the Ag-IIP was 68.51% after one round of photocatalysis and ultrasound, which was closed to three rounds of acid elution. We also conducted an experiment with real wastewater and validated the great potential of Fe₃O₄@SiO₂@TiO₂-IIP in advanced wastewater treatment. The results showed that 1.3 mg of silver was recovered from 100 mL of 50 mg/L AgNO₃ solution with 0.1 g of the IIP. Accordingly, the functionalized IIP constructed and applied in this study demonstrated (a) the promising selective adsorption capacity of Ag, (b) the efficient photoreduction potential of Ag, (c) gentle and ecofriendly regeneration conditions, and (d) excellent magnetic separation ability, and it has great potential in future practical wastewater treatment