The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 ...asymptomatic individuals in the Wanzhou District who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy
. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 15-26 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.6-10.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.8-38.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.
Grain size is an important component trait of grain yield, which is frequently threatened by abiotic stress. However, little is known about how grain yield and abiotic stress tolerance are regulated. ...Here, we characterize GSA1, a quantitative trait locus (QTL) regulating grain size and abiotic stress tolerance associated with metabolic flux redirection. GSA1 encodes a UDP-glucosyltransferase, which exhibits glucosyltransferase activity toward flavonoids and monolignols. GSA1 regulates grain size by modulating cell proliferation and expansion, which are regulated by flavonoid-mediated auxin levels and related gene expression. GSA1 is required for the redirection of metabolic flux from lignin biosynthesis to flavonoid biosynthesis under abiotic stress and the accumulation of flavonoid glycosides, which protect rice against abiotic stress. GSA1 overexpression results in larger grains and enhanced abiotic stress tolerance. Our findings provide insights into the regulation of grain size and abiotic stress tolerance associated with metabolic flux redirection and a potential means to improve crops.
Background
Heidenhain variant of Creutzfeldt–Jakob disease (CJD) remains a diagnostic challenge in clinical practice. We aimed to describe the clinical and prognostic features of Heidenhain cases, ...through a case series study.
Methods
We retrospectively reviewed the definite or probable CJD cases admitted to two tertiary referral university hospitals over a decade to identify Heidenhain cases and investigated their survival status by telephone follow‐up. Their clinical characteristics, neuroimaging features, electroencephalography (EEG) results, cerebrospinal fluid profiles, and PRNP gene mutations were also analyzed.
Results
Of a total of 85 CJD cases, 20 (24%) Heidenhain cases (11 women 55%; median age, 64 years range, 44–72 years) were identified. The median survival time was 22 weeks (range, 5–155 weeks). The median duration of isolated visual symptoms was 3 weeks (range, 1–12 weeks). The most common early visual symptom was blurred vision (16/20, 80%), followed by diplopia (6/20, 30%). The prevalence significantly increased for complex visual hallucination (p = 0.005) and cortical blindness (p = 0.046) as the disease progressed. The positive rate of serial magnetic resonance images (20/20, 100%) was higher than that of serial EEGs (16/20, 80%). Two patients (2/10, 20%) had pathogenic PRNP mutations, E196A and T188K, respectively. Heidenhain cases with PRNP mutations had significantly longer survival time than those without PRNP mutations (p = 0.047).
Conclusions
Besides blurred vision (80%), diplopia (30%) was also a frequent early visual symptom among Heidenhain cases. Heidenhain phenotype can occur in genetic CJD cases. PRNP mutation status might be an important prognostic factor for Heidenhain cases.
We characterized the clinical and prognostic features of Heidenhain variant of Creutzfeldt–Jakob disease (CJD), through the largest Chinese case series (n = 20). Besides blurred vision (80%), diplopia (30%) was also a frequent early visual symptom among Heidenhain cases. Heidenhain phenotype can occur in genetic CJD cases, and PRNP mutation status might be an important prognostic factor for Heidenhain cases.
2D materials hold great potential for designing novel electronic and optoelectronic devices. However, 2D material can only absorb limited incident light. As a representative 2D semiconductor, ...monolayer MoS2 can only absorb up to 10% of the incident light in the visible, which is not sufficient to achieve a high optical‐to‐electrical conversion efficiency. To overcome this shortcoming, a “gap‐mode” plasmon‐enhanced monolayer MoS2 fluorescent emitter and photodetector is designed by squeezing the light‐field into Ag shell‐isolated nanoparticles–Au film gap, where the confined electromagnetic field can interact with monolayer MoS2. With this gap‐mode plasmon‐enhanced configuration, a 110‐fold enhancement of photoluminescence intensity is achieved, exceeding values reached by other plasmon‐enhanced MoS2 fluorescent emitters. In addition, a gap‐mode plasmon‐enhanced monolayer MoS2 photodetector with an 880% enhancement in photocurrent and a responsivity of 287.5 A W−1 is demonstrated, exceeding previously reported plasmon‐enhanced monolayer MoS2 photodetectors.
By dropping Ag shell‐isolated nanoparticles onto Al2O3‐covered Au film, the gap‐mode plasmonic structure with a gap thickness of 7 nm can form naturally. By integrating monolayer MoS2 into this plasmonic structure, 110‐fold photoluminescence and 880% photocurrent enhancement are achieved. This work shows that the gap‐mode plasmonic structures have huge potential for realizing high‐performance 2D‐material‐based optoelectronic devices.
Transition metal‐based nitrogen‐doped carbon (M‐Nx‐C) is considered as a promising catalyst for the oxygen reduction reaction (ORR) in clean energy storage and conversion devices. Herein, ZnCo ...dual‐atomic sites are incorporated in hierarchical N‐doped carbon (HNC), with 1D nanotubes wrapped in 2D nanosheets structure (termed as 1D@2D ZnCo‐HNC), via a one‐step bio‐inspired pyrolysis. The feeding ratio of Zn to Co precursor and pyrolytic temperature are critically modulated to achieve well‐defined morphologies of the products, endowing them with the integrated merits of nanotubes and nanosheets as efficient ORR catalysts. Benefiting from the particular structure and electronic regulation of Zn on Co, the ZnCo‐Nx dual‐atomic system exhibits excellent ORR catalytic characteristics with an onset potential of 1.05 V and a half‐wave potential of 0.82 V. Density functional theory calculations further explain the regulating role of Zn, such that the adjusted Co in ZnCo‐Nx sites significantly reduces the energy cost to ultimately facilitate the ORR. Moreover, the Zn–air battery assembled with ZnCo‐HNC is capable of delivering the maximum power density of 123.7 mW cm−2 and robust stability for 110 h (330 cycles). This method provides a promising strategy for fabricating efficient transition metal‐based carbon catalysts for green energy devices.
With the unique 1D@2D structure and abundant ZnCo dual‐atomic sites, bio‐inspired ZnCo‐HNC exhibits excellent catalytic performances for the oxygen reduction reaction and a home‐assembled Zn–air battery. Density functional theory calculations further demonstrate that Co is the main active center in the ZnCo‐Nx system, while Zn serves as the charge adjuster.
Nowadays, blockchain technology and industry has developed rapidly all over the world, which is inseparable from continuous innovation and improvement on smart contract technology. Therefore, by ...summarizing the working principle and application research status of blockchain smart contract, this paper analyzes the development and challenges of smart contract. Firstly, we introduce the model and operation principle of blockchain smart contract for the overall architecture, analyze the deployment process of smart contract with Ethereum, Hyperledger Fabric and EOSIO, and make a comparative analysis from the technical level. And taking Byteball, InterValue and IOTA platforms as examples, we introduce the deployment process and application potential for DAG-based blockchain smart contract. Additionally, we also summarize the application research of smart contract for international and Blockchain Oracle, and discuss its innovative application and development trend in the future. Secondly, we introduce the application status of smart contract with Ethereum and Hyperledger Fabric platforms from the aspects of financial transactions, Internet of things, medical applications, and supply chain, and further discuss EOS (enterprise operation system), Blockchain Oracle and other application fields. Furthermore, we introduce the application advantages and challenges to smart contract for industrial Internet from the fields of manufacturing, food industry, industrial Internet of things and industry 4.0. Finally, we discuss the challenges faced by smart contract with technical issues, analyzes the impact on large-scale applications and mining system on the sustainable development of smart contract, and looks forward to the future research direction of blockchain smart contract.
Guest‐induced host–guest assembly in metal–organic frameworks (MOFs) has become a critical strategy to achieve circularly polarized luminescence (CPL). Herein, chiral metal–organic clusters (MOCs) ...induced CPL of achiral MOF are reported. Enantiopure titanium‐oxo clusters (R/S‐TOCs) are effectively loaded into the pores of a fluorescent, highly stable MOF NU‐901 thin film by using a liquid‐phase epitaxial layer‐by‐layer encapsulation method. The resulting chiral TOCs@NU‐901 MOF thin films exhibit strong chirality, intense photoluminescence, and excellent CPL performance with the highest dissymmetry factor (±0.025) reported so far for the downshifted MOF‐based materials. Further, the comparison experiments and density functional theory (DFT) calculations demonstrate that the excellent performance benefited from the strong chirality and charge transfer caused by the significant π–π interactions between the host (MOF) and guest (R/S‐TOCs). This novel chiral MOCs induced approach provides a powerful toolbox for new host–guest CPL thin film materials.
Novel chiral guests‐induced metal–organic framework (MOF) thin films by liquid‐phase epitaxial layer‐by‐layer encapsulation strategy for high circularly polarized luminescence (CPL) are reported. Thanks to the chirality and charge transfers caused by the significant π–π interactions in the host–guest combination, the resulting host–guest MOF thin film exhibits excellent CPL with the highest glum (±0.025) among the downshifted MOFs‐based materials.
Background
The development and progression of cancer cachexia are connected to systemic inflammation and physical performance. However, few relevant studies have reported the survival outcomes ...prediction of systemic inflammation and physical performance in patients with colorectal cancer (CRC) cachexia. This study investigated the prognostic prediction value of systemic inflammation and performance status in patients with CRC cachexia.
Methods
This multicentre cohort study prospectively collected 905 patients with CRC (58.3% males, 59.3 ± 11.5 years old). Cancer cachexia was diagnosed according to the 2011 Fearon Cachexia Diagnostic Consensus. The prognostic value of systematic inflammatory indicators was determined using the area under the curve, concordance index, and multivariate survival analysis. Performance status was evaluated with Eastern Coopertive Oncology Group performance score (ECOG‐PS). Survival data were analysed using univariate and multivariate Cox regression analyses.
Results
The area under the curve, concordance index and survival analysis showed that C‐reactive protein (CRP), lymphocyte to CRP ratio (LCR) and CRP to albumin ratio (CAR) were more stable and consistent with the survival of patients with CRC, both in non‐cachexia and cachexia populations. Among patients with CRC cachexia, high inflammation low LCR, hazard ratio (HR) 95% confidence interval (95% CI) = 3.33 (2.08–5.32); high CAR, HR (95% CI) = 2.92 (1.88–4.55); high CRP, HR (95% CI) = 3.12 (2.08–4.67) indicated a worse prognosis, compared with non‐cachexia patients low LCR, HR (95% CI) = 2.28 (1.65–3.16); high CAR, HR (95% CI) = 2.36 (1.71–3.25); high CRP, HR (95% CI) = 2.58 (1.85–3.60). Similarly, among patients with CRC cachexia, high PS ECOG‐PS 2, HR (95% CI) = 1.61 (1.04–2.50); ECOG‐PS 3/4, HR (95% CI) = 2.91 (1.69–5.00) indicated a worse prognosis, compared with patients with CRC without cachexia ECOG‐PS 2, HR (95% CI) = 1.28 (0.90–1.81); ECOG‐PS 3/4, HR (95% CI) = 2.41 (1.32–4.39). Patients with CRC cachexia with an ECOG‐PS score of 2 or 3–4 and a high inflammation had a shorter median survival time, compared with patients with an ECOG‐PS score of 0/1 and a low inflammation.
Conclusions
The systemic inflammatory markers LCR, CAR and CRP have stable prognostic values in patients with CRC. The ECOG‐PS may be an independent risk factor for CRC. Combined evaluation of systemic inflammation and ECOG‐PS in patients with CRC cachexia could provide a simple survival prediction.
Hetero-nanostructures featured with both strong plasmon absorption and high catalytic activity are believed to be ideal platforms to realize efficient light-driven catalysis. However, in reality, it ...remains a great challenge to acquire high-performance catalysis in such hetero-nanostructures due to poor generation and transfer of plamson-induced hot electrons. In this report, we demonstrate that Au nanorod@Pd superstructures (Au@Pd SSs), where the ordered Pd nanoarrays are precisely grown on Au nanorod surfaces via solution-based seed-mediated approach, would be an excellent solution for this challenge. Both experiment and theory disclose that the ordered arrangement of Pd on Au nanorod surfaces largely promotes hot electron generation and transfer via amplified local electromagnetic field and decreased electron–phonon coupling, respectively. Each effect is separately highlighted in experiments by the significant plasmon-enhanced catalytic activity of Au@Pd SSs in two types of important reactions with a distinct time scale of bond-dissociation event: molecular oxygen activation and carbon–carbon coupling reaction. This work opens the door to design and application of new generation photocatalysts.
Cognitive decline is one of the complications of type 2 diabetes (T2D). Intermittent fasting (IF) is a promising dietary intervention for alleviating T2D symptoms, but its protective effect on ...diabetes-driven cognitive dysfunction remains elusive. Here, we find that a 28-day IF regimen for diabetic mice improves behavioral impairment via a microbiota-metabolites-brain axis: IF enhances mitochondrial biogenesis and energy metabolism gene expression in hippocampus, re-structures the gut microbiota, and improves microbial metabolites that are related to cognitive function. Moreover, strong connections are observed between IF affected genes, microbiota and metabolites, as assessed by integrative modelling. Removing gut microbiota with antibiotics partly abolishes the neuroprotective effects of IF. Administration of 3-indolepropionic acid, serotonin, short chain fatty acids or tauroursodeoxycholic acid shows a similar effect to IF in terms of improving cognitive function. Together, our study purports the microbiota-metabolites-brain axis as a mechanism that can enable therapeutic strategies against metabolism-implicated cognitive pathophysiologies.
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