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Cromileptes altivelis, humpback grouper, belongs to the family Epinephelidae and is one popular farmed fish species because of its high economic value and ornamental value. However, more and more diseases outbreaks have been reported with C. altivelis aquaculture. Today, a new brain cell line of C. altivelis (named CAB) was established and characterized. Our results showed that CAB cells were suitable for growth at 26 °C in L-15 medium supplemented with 15% fetal bovine serum (FBS). The results of 18S rRNA gene sequencing confirmed that CAB cell line was derived from C. altivelis. Moreover, chromosomal aneuploidy was observed in CAB cells, and the modal chromosome number of CAB cells was 48 by chromosome analysis. In addition, CAB cells could transfect pEGFP-N3 plasmid with high transfection efficiency, indicating that CAB cell line has the potential to investigate the function of exogenous genes in vitro. Furthermore, the bacterial susceptibility results suggested that CAB cells were susceptive to Vibrio harveyi and Edwardsiella tarda. And, heavy metals (Hg, Cd, and Cu) were toxic to the CAB cells, and the toxic effect was dose-dependent. In summary, the CAB cell line could be a powerful tool in vitro to study functional genes and has the potential application in bacterial susceptibility and toxicology.

Horizontal gene transfer is a ubiquitous force in microbial evolution. Previous studies have shown that the human gut is a hot spot for gene transfer between species, but the more subtle exchange of variation within species – collectively known as recombination – remains poorly characterized in this ecosystem. Here, we show that the genetic structure of the human gut microbiome provides unique opportunities to measure individual recombination events directly, enabling quantitative comparisons of recombination across a diverse range of species that inhabit a common environment. By analyzing a large collection of recent recombination events in the core genomes of 29 gut commensals, we uncovered systematic heterogeneities in the rates and lengths of transferred segments, which are difficult to explain by existing models of ecological isolation or reduced efficiencies of recombination. We also find that natural selection plays a role in facilitating the spread of genetic variants onto different strain backgrounds, both within individual hosts and across the broader global population. These results shed light on the dynamics of in situ recombination, which place important constraints on the adaptability of gut microbial communities.

Tumor necrosis factor ligand superfamily member 6 (TNFSF6), also known as FasL/CD95L, is essential for maintaining the body's immune homeostasis. However, the current reports on TNFSF6 in fish are relatively scarce. In the present study, we conducted functional analyses of a TNFSF6 (TroTNFSF6) from the teleost fish golden pompano (Trachinotus ovatus). TroTNFSF6 is composed of 228 amino acids and has a low similarity with other species (9.65%-58.79%). TroTNFSF6 was expressed in the 11 tissues tested and was significantly up-regulated after Edwardsiella tarda infection. In vivo, overexpression of TroTNFSF6 effectively stimulated the AKP and ACP activities, and reduced bacterial infection in fish tissues. Correspondingly, knockdown of TroTNFSF6 expression resulted in increasing bacterial dissemination and colonization in fish tissues. In vitro, recombinant TroTNFSF6 protein promoted the proliferation of T. ovatus head kidney lymphocytes (HKLs), and promoted the apoptosis of murine liver cancer cells (Hepa1-6). The results indicated that TroTNFSF6 plays an important role in the T. ovatus antibacterial immunity. These observations will facilitate the future in-depth study of teleost TNFSF6.

Phylogenetic trees describe both the evolutionary process and community diversity. Recent work has established that they exhibit scale-invariant topology, which quantifies the fact that their branching lies in between the two extreme cases of balanced binary trees and maximally unbalanced ones. In addition, the backbones of phylogenetic trees exhibit bursts of diversification on all timescales. Here, we present a simple, coarse-grained statistical model of niche construction coupled to speciation. Finite-size scaling analysis of the dynamics shows that the resultant phylogenetic tree topology is scale-invariant due to a singularity arising from large niche construction fluctuations that follow extinction events. The same model recapitulates the bursty pattern of diversification in time. These results show how dynamical scaling laws of phylogenetic trees on long timescales can reflect the indelible imprint of the interplay between ecological and evolutionary processes.

The thermodynamics on the direct synthesis of dimethyl carbonate (DMC) from CO2 and CH3OH was calculated and analyzed. Using Y(NO3)3·6H2O as the precursor, a series of Y2O3 were prepared through th...

Due to the strong exothermic/endothermic effect during the H2 absorption/desorption process, the design of metal hydride reactors has become a hot research topic to improve the rate of hydrogenation/dehydrogenation. Herein, based on bionic optimization and the constructal theory, a novel duplex helical elliptical tube reactor (DHER) is proposed for enhancing the heat transfer and reaction performances of metal hydride reactors. DHER displayed outstanding performances among 5 types of reactors, and the maximal temperature difference could be reduced by 5.1 K/5.6 K during the H2 absorption/desorption. The parameters of DHER were designed and optimized with the spiral diameter (Dc) = 10 mm, elliptical major axis (A) = 4 mm, elliptical minor axis (B) = 2 mm, pitch (Pt) = 13 mm, tilt angle (α) = 45°, and installation angle (β) = 180°. The sensitivity analysis for DHER is investigated, and the sequential effects of the structural parameters on the reaction performance followed the order of Dc > A > B > Pt > α. Through a comparative analysis of geometrical characteristics of the structural parameters and the reaction performance of the reactor, the results indicated that the radial projected area of the heat exchange tube is the dominant factor in the reaction performance of DHER. Moreover, the surface was calculated based on the sensitivity analysis data and fitted by the quadratic response surface regression model to predict the reaction time under different structural parameters, which may provide guidance for the design of reactors. In addition, the hydriding and dehydriding cyclic processes without preheating and precooling stages were confirmed to have prominent and reliable performances for DHER, attaining only 1227 s under its optimal cycle conditions during absorption (0.8 MPa, 273.15 K) and desorption (0.1 MPa, 373.15 K).

In Fall 2020, universities saw extensive transmission of SARS-CoV-2 among their populations, threatening health of the university and surrounding communities, and viability of in-person instruction. Here we report a case study at the University of Illinois at Urbana-Champaign, where a multimodal “SHIELD: Target, Test, and Tell” program, with other non-pharmaceutical interventions, was employed to keep classrooms and laboratories open. The program included epidemiological modeling and surveillance, fast/frequent testing using a novel low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD, and digital tools for communication and compliance. In Fall 2020, we performed >1,000,000 covidSHIELD tests, positivity rates remained low, we had zero COVID-19-related hospitalizations or deaths amongst our university community, and mortality in the surrounding Champaign County was reduced more than 4-fold relative to expected. This case study shows that fast/frequent testing and other interventions mitigated transmission of SARS-CoV-2 at a large public university.

In the Fall of 2020, many universities saw extensive transmission of SARS-CoV-2 among their populations, threatening the health of students, faculty and staff, the viability of in-person instruction, and the health of surrounding communities.1, 2 Here we report that a multimodal “SHIELD: Target, Test, and Tell” program mitigated the spread of SARS-CoV-2 at a large public university, prevented community transmission, and allowed continuation of in-person classes amidst the pandemic. The program combines epidemiological modelling and surveillance (Target); fast and frequent testing using a novel and FDA Emergency Use Authorized low-cost and scalable saliva-based RT-qPCR assay for SARS-CoV-2 that bypasses RNA extraction, called covidSHIELD (Test); and digital tools that communicate test results, notify of potential exposures, and promote compliance with public health mandates (Tell). These elements were combined with masks, social distancing, and robust education efforts. In Fall 2020, we performed more than 1,000,000 covidSHIELD tests while keeping classrooms, laboratories, and many other university activities open. Generally, our case positivity rates remained less than 0.5%, we prevented transmission from our students to our faculty and staff, and data indicate that we had no spread in our classrooms or research laboratories. During this fall semester, we had zero COVID-19-related hospitalizations or deaths amongst our university community. We also prevented transmission from our university community to the surrounding Champaign County community. Our experience demonstrates that multimodal transmission mitigation programs can enable university communities to achieve such outcomes until widespread vaccination against COVID-19 is achieved, and provides a roadmap for how future pandemics can be addressed.

Cromileptes altivelis, humpback grouper, belongs to the family Epinephelidae and is one popular farmed fish species because of its high economic value and ornamental value. However, more and more diseases were outbreak with the increasing of C. altivelis breeding, resulting in severe economic losses. Today, a new brain cell line of C. altivelis (CAB) was established and has been subcultured for more than 40 passages until now. Our results showed that the morphology of CAB cells is epithelial-like and suitable for growth at 26 °C in L15 medium supplemented with 15% fetal bovine serum (FBS). The results of 18S rRNA gene sequencing confirmed that CAB cell line was derived from C. altivelis. Moreover, CAB cells were apparently diploid number of chromosomes (2n = 48) by chromosome analysis. In addition, CAB cells could transfect pEGFP-N3 plasmid with high transfection efficiency, indicating that CAB cell line has the potential to investigate the function of exogenous genes in vitro. Furthermore, the bacterial susceptibility results suggested that CAB cells were susceptive to Vibrio harveyi and Edwardsiella tarda. And, heavy metals (Hg, Cd, and Cu) were toxic to the CAB cells and the toxic effect was dose-dependent. In summary, the CAB cell line could be a powerful tool in vitro to study functional genes and has the potential application in bacterial susceptibility and toxicology.

SummaryWe have performed detailed modeling of the COVID-19 epidemic within the State of Illinois at the population level, and within the University of Illinois at Urbana-Champaign at a more detailed level of description that follows individual students as they go about their educational and social activities.We ask the following questions:How many COVID-19 cases are expected to be detected by entry screening?Will this initial “bump” in cases be containable using the mitigation steps being undertaken at UIUC?Our answers are:Assuming that there are approximately 45,000 students returning to campus in the week beginning August 15, 2020, our most conservative estimate predicts that a median of 270 ± 90 (minimum-maximum range) COVID-19 positive cases will be detected by entry screening. The earliest estimate for entry screening that we report was made on July 24th and predicted 198 ± 90 (68% CI) positive cases.If the number of returning students is less, then our estimate just needs to be scaled proportionately.This initial bump will be contained by entry screening initiated isolation and contact tracing, and once the semester is underway, by universal masking, a hybrid teaching model, twice-weekly testing, isolation, contact tracing, quarantining and the use of the Safer Illinois exposure notification app.

Steric hindrance engineering is of great significance to the preparation of new stable organic cations and durable polymeric anion exchange membrane materials. In this work, we presented a study of the structure-property relationship in quaternized poly (2,6-dimethyl-1,4-phenylene oxide) containing bulky n-propyl, isopropyl, or cyclohexyl-functionalized quaternary ammonium moieties. To our surprise, PPO-iP membranes possessing isopropyl-based QA cations showed higher water uptake than n-propyl- and cyclohexyl-containing analogues (PPO-nP and PPO-CH), in which obvious microphase-separated morphology was found. Thus, PPO-iP membranes displayed the highest hydroxide conductivity at 20 °C in water (37.3 mS/cm, IEC = 1.90 mmol/g). A standard protocol (1 M or 2 M NaOH at 60 °C) was used to determine the chemical stability of model cations and membranes both having sterically crowded QAs. Minor loss (

Benzyltrimethylammonium (BTMA) is most frequently-used organic cations in anion exchange membrane (AEM) materials. However, BTMA-based AEMs always suffer from low ionic conductivity and insufficient alkaline stability for practical alkaline fuel cells. Here, we present a systematic investigation of a series of side-chain-type poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) AEMs with constitutional isomerism in BTMA cations. Three isomeric BTMA cations, e.g. meta-BTMA, ortho-BTMA, and para-BTMA, were tethered onto PPO backbones via a flexible spacer using CuAAC reaction, producing side-chain-type AEMs, namely m-QPPO, o-QPPO, and p-QPPO membranes, respectively. As expected, side-chain-type PPO AEMs displayed higher hydroxide conductivity as compared to a control PPO-QA membrane where BTMA cations were directly linked on PPO backbones, due to the microphase-separated morphologies as confirmed by small-angle X-ray scattering (SAXS) results. Although these isomeric quaternized PPO copolymers had identical chemical composition and polymer architectures, they did not share similar properties. Specifically, among three side-chain-type AEMs, the highest hydroxide conductivity of 42.8 mS/cm was observed for m-QPPO membrane having meta-BTMA cations with an ion exchange capacity of 1.93 meq./g at 20 °C, as a result of its high water uptake. In addition to high conductivity, m-QPPO membrane showed superior alkaline stability with respect to o-QPPO and p-QPPO membranes. After 200 h of aging in 1 M NaOH at 60 °C, 85% of the hydroxide conductivity was retained for m-QPPO AEMs, while more than 30% conductivity loss was observed for o-QPPO and p-QPPO membranes. NMR analysis of the aged membrane suggested that SN2 nucleophilic substitution at benzyl groups is the dominant degradation mechanisms. Furthermore, the AEM fuel cells using these PPO AEMs with isomeric BTMA cations were investigated, and the cell with highly conductive and durable m-QPPO membranes exhibited the best performance with a peak power density of 333 mW/cm2 at a current density of 700 mA/cm2 at 60 °C, comparable to other AEMFCs with PPO-based AEMs. Consequently, this work not only provides a facile and effective strategy to precisely synthesize isomeric AEMs, but also contributes to fundamental insights into the structure-property relationship as well as alkaline fuel cell performance for these isomeric BTMA-based AEMs, which are not explored before.

Prognostics and health management (PHM) can ensure that a battery system is working safely and reliably. Remaining useful life (RUL) prediction, as one main approach of PHM, provides early warning of failures that can be used to determine the necessary maintenance and replacement of batteries in advance. The existing RUL prediction techniques for lithium-ion batteries are inefficient to learn the long-term dependencies of aging characteristics with the degradation evolution. This paper investigates deep-learning-enabled battery RUL prediction. The long short-term memory (LSTM) recurrent neural network (RNN) is employed to learn the capacity degradation trajectories of lithium-ion batteries. The LSTM RNN is adaptively optimized using the resilient mean square back-propagation method. The developed LSTM RNN is able to capture the underlying long-term dependencies among the degraded capacities such that an explicitly capacity-oriented RUL predictor is constructed. Experimental data from one lithium-ion battery cell is deployed for model construction and verification. This is the first known application of deep learning theory to battery RUL predictions.

We study the effect of a rare earth (RE) catalyst on the kinetics of gas carburizing of 08F and 8620 steels. Carburizing was conducted in a sealed-quench furnace employing an endothermic atmosphere with and without RE addition at 900°C for different times. These experimental results show that compared with conventional gas carburizing the incorporation of RE leads to an obvious increase in layer depth and carbon (C) concentration profile under the same carburizing condition. Cerium (Ce) existing in the carburizing atmosphere and diffusing into the surface layer does not change the kinetics law of carburized layer growth. In addition, the calculated results show that the reaction constant and the diffusion coefficient of carbon between the gas–solid interface can also be increased during RE carburizing.